Infrared detecting device

ABSTRACT

An infrared detecting device includes: an infrared sensor that has one or more infrared detection elements arranged in one or more columns; and an IC chip that performs signal processing on a signal output from the infrared sensor. The infrared sensor and the IC chip are generally juxtaposed in a direction along a scan rotation axis of the infrared sensor.

BACKGROUND

1. Technical Field

The present disclosure relates to an infrared detecting device that iscapable of detecting infrared rays.

2. Description of the Related Art

There are proposed technologies in which an infrared sensor is attachedto an air-conditioning apparatus, such as a room air conditioner, andtwo-dimensional thermal-image data obtained by the infrared sensor isused to perform air conditioning (see, for example, Japanese Patent No.5111417, which is hereinafter referred to as “Patent Document 1”).

Patent Document 1 discloses a technology in which air-conditioningequipment installed at a height of 1800 mm from the floor surface of aroom is provided with an infrared sensor having light-receiving elementsarranged in a vertical line.

SUMMARY

In one general aspect, the techniques disclosed here feature an infrareddetecting device that includes: an infrared sensor that has one or moreinfrared detection elements arranged in one or more columns; and an ICchip that performs signal processing on a signal output from theinfrared sensor. The infrared sensor and the IC chip are generallyjuxtaposed in a direction along a scan rotation axis of the infraredsensor.

According to the present disclosure, it is possible to provide aninfrared detecting device that can increase a detection range in an areanear and below the position where the infrared detecting device isdisposed.

Additional benefits and advantages of the disclosed embodiments willbecome apparent from the specification and drawings. The benefits and/oradvantages may be individually obtained by the various embodiments andfeatures of the specification and drawings, which need not all beprovided in order to obtain one or more of such benefits and/oradvantages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating one example of the configuration of aninfrared detecting device in a first embodiment;

FIG. 2 is a schematic view of a physical configuration when the infrareddetecting device in the first embodiment is attached to a housing;

FIG. 3 is a schematic view illustrating a state in which the housing towhich the infrared detecting device in the first embodiment is attachedis installed;

FIG. 4 is a schematic view illustrating the physical configuration ofthe infrared detecting device in the first embodiment;

FIG. 5A is a schematic view of a physical configuration when an infrareddetecting device in a comparative example is attached to the housing;

FIG. 5B is a schematic view for describing a dead angle area of theinfrared detecting device in comparative example illustrated in FIG. 5A;

FIG. 6 is a schematic view for describing that distortion occurs in athermal image acquired by scanning performed by the infrared sensor inthe first embodiment;

FIG. 7 is a diagram illustrating one example of the configuration of aninfrared sensor in a second embodiment;

FIG. 8A is a diagram for describing a relationship of the dimensions ofhorizontal edges of adjacent infrared detection elements in the secondembodiment;

FIG. 8B is a diagram illustrating a relationship of the dimensions ofthe horizontal edges of the adjacent infrared detection elements in thesecond embodiment;

FIG. 8C is a diagram for describing a relationship of the dimensions ofthe horizontal edges of the adjacent infrared detection elements in thesecond embodiment;

FIG. 8D is a diagram illustrating a relationship of the dimensions ofthe horizontal edges of the adjacent infrared detection elements in thesecond embodiment;

FIG. 9 is a diagram illustrating another example of the configuration ofthe infrared sensor in the second embodiment;

FIG. 10 is a diagram illustrating one example of the configuration of aninfrared sensor in a first modification of the second embodiment;

FIG. 11A is a diagram illustrating one example of the configuration ofan infrared sensor in a second modification of the second embodiment;

FIG. 11B is a diagram illustrating another example of the configurationof the infrared sensor in the second modification of the secondembodiment;

FIG. 12A is a diagram illustrating one example of the configuration ofan infrared sensor in a third modification of the second embodiment;

FIG. 12B is a diagram illustrating another example of the configurationof the infrared sensor in the third modification of the secondembodiment;

FIG. 13 is a diagram illustrating one example of the configuration of aninfrared sensor in a fourth modification of the second embodiment;

FIG. 14 is a diagram illustrating one example of the configuration of aninfrared sensor in a fifth modification of the second embodiment;

FIG. 15 is a diagram illustrating another example of the configurationof the infrared sensor in the fifth modification of the secondembodiment;

FIG. 16 is a table illustrating one example of infrared detectionelements constituting the infrared sensor in the fifth modification ofthe second embodiment;

FIG. 17 is a schematic view of a physical configuration when an infrareddetecting device in a third embodiment is attached to the housing;

FIG. 18 is a diagram illustrating one example of the configuration of aninfrared detecting device in a fourth embodiment;

FIG. 19A is a diagram illustrating one example of the configuration aninfrared detector and a scanner in the fourth embodiment;

FIG. 19B is a diagram illustrating one example of the configuration ofan infrared sensor in the fourth embodiment;

FIG. 20 is a diagram illustrating one example of an infrared sensor inan illustrative example of the fourth embodiment;

FIG. 21 is a diagram for describing an inclination of the infraredsensor illustrated in FIG. 20;

FIG. 22A is a diagram for describing an advantage of the infrareddetecting device when an infrared sensor in a comparative example isused;

FIG. 22B is a diagram for describing an advantage of the infrareddetecting device when the infrared sensor illustrated in FIG. 20 isused;

FIG. 23 is a flowchart illustrating an operation of the infrareddetecting device in the fourth embodiment;

FIG. 24 is a diagram illustrating one example of the configuration of aninfrared sensor in a modification of the fourth embodiment;

FIG. 25 is a diagram illustrating one example of the configuration of aninfrared sensor in another example of the modification of the fourthembodiment;

FIG. 26 is a diagram illustrating a configuration example of one exampleof an infrared sensor in a fifth embodiment;

FIG. 27 is a diagram for describing an inclination of the infraredsensor illustrated in FIG. 25;

FIG. 28 is a diagram illustrating one example of the configuration of aninfrared sensor in an illustrative example of the fifth embodiment;

FIG. 29 is a diagram for describing an inclination of the infraredsensor illustrated in FIG. 28;

FIG. 30 is a diagram for describing an advantage of the infrareddetecting device when the infrared sensor illustrated in FIG. 27 isused;

FIG. 31 is a diagram illustrating one example of the configuration of aninfrared detecting device in a sixth embodiment;

FIG. 32 is a partial schematic view of a physical configuration when theinfrared detecting device in the sixth embodiment is attached to thehousing;

FIG. 33A is a schematic view illustrating a physical configuration ofthe infrared detecting device in the sixth embodiment;

FIG. 33B is a schematic view illustrating another physical configurationof the infrared detecting device in the sixth embodiment;

FIG. 34 is an exploded perspective view of an infrared detector in thesixth embodiment;

FIG. 35 is a schematic sectional view of the infrared detector in thesixth embodiment;

FIG. 36 is a circuit block diagram of an IC chip in the sixthembodiment;

FIG. 37 is a schematic view illustrating one example of an arrangementof infrared detection elements constituting an infrared sensor in thesixth embodiment;

FIG. 38 is a schematic view illustrating one example of the arrangementof the infrared detection elements constituting the infrared sensor inthe sixth embodiment;

FIG. 39A is a schematic diagram illustrating one example of thearrangement of the infrared detection elements constituting the infraredsensor in the sixth embodiment;

FIG. 39B is a schematic view illustrating one example of the arrangementof the infrared detection elements constituting the infrared sensor inthe sixth embodiment;

FIG. 39C is a schematic view illustrating one example of the arrangementof the infrared detection elements constituting the infrared sensor inthe sixth embodiment;

FIG. 40A is a schematic view for describing influences of heat from anIC chip during scanning in the comparative example;

FIG. 40B is a schematic view for describing influences of heat from theIC chip during scanning in the infrared detecting device in the sixthembodiment;

FIG. 41A is a schematic view illustrating an example of an arrangementof thermistors in the sixth embodiment;

FIG. 41B is a schematic view illustrating one example of an arrangementof thermistors in the sixth embodiment;

FIG. 42A illustrates one example of the shape of the infrared detectionelements constituting the infrared sensor; and

FIG. 42B illustrates one example of the shape of the infrared detectionelements constituting the infrared sensor.

DETAILED DESCRIPTION Knowledge Underlying Present Disclosure

In the technology disclosed in Patent Document 1, since the infraredsensor is provided at a position above measurement objects, such aspeople and heat sources, there is a problem in that the area near andbelow the infrared sensor is not in a detection range.

In view of the foregoing problem, the present disclosure provides aninfrared detecting device that can increase the detection range in thearea near and below the position where the infrared detecting device isdisposed.

An infrared detecting device and so on according to one aspect of thepresent disclosure will be described in detail with reference to theaccompanying drawings. Embodiments described below all representspecific examples of the present disclosure. Numerical values, shapes,materials, constituent elements, the arrangement positions ofconstituent elements, and so on described in the embodiments below aremerely examples and are not intended to limit the present disclosure. Ofthe constituent elements in the embodiments below, constituent elementsnot set forth in the independent claims that represent the broadestconcept will be described as optional constituent elements.

First Embodiment

[Configuration of Infrared Detecting Device]

An infrared detecting device in a first embodiment will be describedbelow with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating one example of the configuration of aninfrared detecting device in the first embodiment. FIG. 2 is a schematicview of a physical configuration when the infrared detecting device inthe present embodiment is attached to a housing. FIG. 3 is a schematicview illustrating a state in which the housing to which the infrareddetecting device in the present embodiment is attached is installed.FIG. 4 is a schematic view illustrating the physical configuration ofthe infrared detecting device in the present embodiment.

An infrared detecting device 1 is attached to a housing 2, which isinstalled on an installation surface 41 that is generally orthogonal toa bottom surface 42 of space 4 and that is located at a predeterminedheight from the bottom surface 42, as illustrated in FIG. 3, to acquirea thermal image of a detection range. The “thermal image” as used hereinrefers to an image constituted by a plurality of pixels indicating thedistribution of temperatures in a temperature detection range. The“predetermined height” refers to, for example, a height that is largerthan a temperature detection targets (measurement targets), such aspeople or heat sources, and is, for example, 1800 mm or more. Thehousing 2 is, for example, the housing of air-conditioning equipment,such as an air conditioner. The housing 2 analyzes states in a room,such as the positions of people, the positions of heat sources, and athermal sensation, by using the thermal image acquired by the infrareddetecting device 1 and controls any of a blowing direction, an airvolume, a temperature, and a humidity on the basis of the analyzedstates in the room. The space 4 is, for example, a room, the bottomsurface 42 is, for example, the floor surface of the room, and theinstallation surface 41 is, for example, a wall surface of a room.

As illustrated in FIG. 1, the infrared detecting device 1 includes aninfrared detector 10, a scanner 11, and a control processor 12.

The scanner 11 has a scan rotation axis S1 (illustrated in FIG. 3) androtates an infrared sensor 102 about the scan rotation axis S1 tothereby cause the infrared sensor 102 to scan the space 4. The scanrotation axis S1 is generally parallel to the installation surface 41.In the present embodiment, the scanner 11 includes a motor 111 and amount base 112, as illustrated in FIGS. 2 to 4.

Under the control of the control processor 12, the motor 111 rotates themount base 112 about the scan rotation axis S1 to thereby cause theinfrared sensor 102 to rotate about the scan rotation axis S1. The motor111 is, for example, a stepping motor or a servo motor.

A sensor module 101, described below, is mounted on the mount base 112.The mount base 112 is disposed so as to have an inclination relative tothe scan rotation axis S1. The inclination may be, for example, about30°.

The scanner 11 rotates the infrared detector 10 about the scan rotationaxis S1 to thereby cause the infrared detector 10 to scan a temperaturedetection range in the space 4. In the present embodiment, the infrareddetector 10 includes the sensor module 101, which has the infraredsensor 102, and a cover 103, as illustrated in FIGS. 2 to 4.

The sensor module 101 is provided with a lens (not illustrated) inaddition to the infrared sensor 102 and is electrically connected to thehousing 2 through a wiring line 104 (illustrated in FIG. 2). The sensormodule 101 is attached to the mount base 112 of the scanner 11.

The lens (not illustrated) is made of silicon or zinc sulfide (ZnS)having a high infrared transmittance. The lens is designed so thatinfrared rays (infrared light) that enter the lens from individualdirections are incident on one or more infrared detection elementsconstituting the infrared sensor 102.

The infrared sensor 102 is rotated about the scan rotation axis S1, asillustrated in FIG. 4, to scan the temperature detection range in thespace 4 and outputs thermal images (infrared terminal images) of thescanned temperature detection range to the control processor 12. Morespecifically, the infrared sensor 102 is constituted by one or moreinfrared detection elements arranged in one or more columns and detectsinfrared rays in the temperature detection range in the space 4 scannedby the one or more infrared detection elements.

The arrangement plane of the one or more infrared detection elements isarranged so as to have an inclination relative to the installationsurface 41. In other words, the arrangement plane is arranged so as tohave an inclination relative to the scan rotation axis S1. The center (alens center) of the arrangement plane has a rotation center throughwhich the scan rotation axis S1 passes, that is, a rotation center whenthe infrared sensor 102 is rotated about the scan rotation axis S1. Inaddition, the arrangement plane intersects the scan rotation axis S1.Thus, for example, as illustrated in FIG. 3, a central axis C1 of thefield of view of the infrared sensor 102 is directed from the directionorthogonal to the installation surface 41 toward the bottom surface 42,that is, is directed downward.

Now, a comparative example will be described.

FIG. 5A is a schematic view of a physical configuration when an infrareddetecting device in a comparative example is attached to the housing.FIG. 5B is a schematic view for describing a dead angle area of theinfrared detecting device in the comparative example illustrated in FIG.5A. Elements that are the same as or similar to those in FIG. 3 aredenoted by the same reference numerals, and detailed descriptionsthereof are not given hereinafter.

In the infrared detecting device in the comparative example illustratedin FIGS. 5A and 5B, a mount base 512, a sensor module 501 mounted on themount base 512, and an infrared sensor 502 provided on the sensor module501 are arranged along (parallel to) the scan rotation axis S1, unlikethe infrared detecting device 1 in the present embodiment. Theconfiguration of the mount base 512, the sensor module 501, and theinfrared sensor 502 in the comparative example is substantially the sameas that of the mount base 112, the sensor module 101, and the infraredsensor 102 in the present embodiment, except for the above-describedarrangement, and thus detailed descriptions thereof are not givenhereinafter.

As illustrated in FIG. 5B, a central axis C2 of the field of view of theinfrared sensor 502 is parallel to the direction orthogonal to theinstallation surface 41 (i.e., is parallel to the bottom surface 42). Asillustrated in FIGS. 5A and 5B, the scan rotation axis S1 passes alongthe arrangement plane of the infrared sensor 502, and the infraredsensor 502 is rotated about the scan rotation axis S1 that passes alongthe arrangement plane. Thus, an area A1 below a lowest-end main lightray V3, which is a main light ray at a lowest end that is included inthe effective viewing angle (angle of view) of the infrared sensor 502and that is the closest to the bottom surface 42 is in a dead angle,that is, is out of the range of detection.

On the other hand, as illustrated in FIGS. 3 and 4, the infrared sensor102 in the present embodiment is arranged with an inclination relativeto the scan rotation axis S1, the scan rotation axis S1 passes throughthe center of the infrared sensor 102, and the scan rotation axis S1 andthe infrared sensor 102 intersect each other. Thus, the central axis C1of the field of view of the infrared sensor 102 is inclined downward.That is, the central axis C1 of the field of view of the infrared sensor102 is inclined more downward than the central axis C2 of the field ofview of the infrared sensor 502. Thus, the infrared sensor 102 isrotated about the scan rotation axis S1, with the central axis C1 of thefield of view being maintained at the same angle relative to the bottomsurface 42.

Thus, the area near and below the position where the infrared sensor 102is disposed is included in the effective viewing angle (angle of view).In other words, the area located in a dead angle and below a lowest-endmain light ray V2, which is a main light ray at a lowest end that isincluded in the effective viewing angle (angle of view) of the infraredsensor 102 and that is the closest to the bottom surface 42, is reduced,compared with that in the infrared sensor 502 in the comparativeexample. Thus, the infrared sensor 102 in the present embodiment canincrease the detection range in the area near and below the positionwhere the infrared sensor 102 is disposed.

The cover 103 is made of infrared transmitting material, such aspolyethylene or silicon, and covers the infrared sensor 102 (the lens).

The control processor 12 controls the scanner 11, processes thermalimages (input images) acquired by the infrared detector 10, and outputsa resulting thermal image to a computing device included in the housing2. The control processor 12 may be included in the computing device inthe housing 2.

In this case, the control processor 12 performs distortion correction onthe thermal images acquired by the infrared detector 10 and thenperforms processing for obtaining thermal-image data indicating thepositions and the temperatures of heat sources in the temperaturedetection range on the basis of the thermal image on which distortioncorrection is performed. Examples of the positions and the temperaturesof the heat sources include the positions of people, the temperatures ofa user's hand and face, and the temperatures of walls. This is because,when the infrared sensor 102 is rotated about the scan rotation axis S1,the thermal image output from the infrared sensor 102 has distortion,since the rotational speeds (rotational pitches) of an upper end and alower end of the infrared sensor 102, when viewed from the bottomsurface 42, differ from each other.

The control processor 12 may generate a high-definition thermal image(an output image) by performing super resolution processing on thethermal images (input images) acquired by the infrared detector 10 andrecombining the thermal images (the input images). In this case, thecontrol processor 12 can output the generated high-definition thermalimage, that is, the thermal image on which the super resolutionprocessing is performed. The “super resolution processing” as usedherein is one type of resolution-enhancement processing that cangenerate high-resolution information (an output image) that is notincluded in an input image. A processing method for acquiring a singlehigh-resolution image from a plurality of images and a processing methodusing learning data are available as the super resolution processing. Inthe present embodiment, the scanner 11 causes the infrared detector 10to perform scanning to thereby allow acquisition of a thermal image(with sub-pixel position displacement) of a temperature detection range,that is, thermal-image data of different sample points.

Advantages, Etc. of First Embodiment

As described above, the infrared detecting device in the presentembodiment includes the infrared sensor whose central axis of the fieldof view is inclined relative to the scan rotation axis S1. This makes itpossible to increase the detection range in the area near and below theposition where the infrared detecting device in the present embodimentis disposed.

Second Embodiment

Although a case in which the control processor 12 performs distortioncorrection processing on the thermal image output from the infraredsensor 102 has been described above in the first embodiment, the presentdisclosure is not limited thereto. One or more infrared detectionelements constituting the infrared sensor 102 may be formed consideringthe inclination relative to the scan rotation axis S1, to eliminate theneed for the control processor 12 to perform the distortion correctionprocessing. Such a case will be described below.

FIG. 6 is a schematic view for describing that distortion occurs in athermal image acquired through scanning performed by the infrared sensorin the first embodiment.

When the infrared sensor 102 is rotated about the scan rotation axis S1,the rotational speeds (rotational pitches) of an upper end and a lowerend of the infrared sensor 102, when viewed from the bottom surface 42,differ from each other. For example, it is assumed that the infraredsensor 102 is constituted by infrared detection elements arranged in amatrix, and the sizes of the infrared detection elements are equal toeach other. In this case, since the rotational speed of the infrareddetection elements in the row at the upper end is higher than therotational speed of the infrared detection elements in the row at thelower end, the scan density (resolution) at the upper end (indicated byD1 in FIG. 6) is lower than that at the lower end (indicated by D2 inFIG. 6). That is, the scan area covered by one infrared detectionelement at the upper end (indicated by D1 in FIG. 6) is larger than thatcovered by one infrared detection element at the lower end (indicated byD2 in FIG. 6). In this case, the control processor 12 corrects (performsdistortion correction on) differences between the scan densities(resolutions) of the infrared detection elements at the upper end andthe lower end, to thereby make the resolutions of thermal imagesacquired to become equal to each other.

In the present embodiment, the horizontal dimensions of the infrareddetection elements (pixels) constituting the infrared sensor are changedso that the control processor 12 does not need to perform the distortioncorrection. A description will be given in detail.

[Configuration of Infrared Sensor]

FIG. 7 is a diagram illustrating one example of the configuration of aninfrared sensor in a second embodiment.

An infrared sensor 202 in the present embodiment has a plurality ofinfrared detection elements arranged in one or more columns and isformed such that a horizontal edge of each of the infrared detectionelements in each column, the horizontal edge being generally parallel tothe bottom surface 42, has a smaller dimension as the infrared detectionelement is located closer to the bottom surface 42. FIG. 7 illustratesone example of the infrared sensor 202 that is formed such that aplurality of infrared detection elements are arranged in one column, andthe horizontal edge of each of the infrared detection elements, thehorizontal edge being generally parallel to the bottom surface 42, has asmaller dimension as the infrared detection element is located closer tothe bottom surface 42.

Now, a description will be given of a relationship of the dimensions ofthe horizontal edges of adjacent infrared detection elements.

FIGS. 8A to 8D are diagrams for describing a relationship of thedimensions of the horizontal edges of adjacent infrared detectionelements in the second embodiment. Elements that are the same as orsimilar to those in FIGS. 2 and 3 are denoted by the same referencenumerals, and detailed descriptions thereof are not given hereinafter.FIG. 8A conceptually illustrates the field of view (FOV), that is, theeffective viewing angle (angle of view), of the infrared sensor 202.FIG. 8B conceptually illustrates an example in which n infrareddetection elements that constitute the infrared sensor 202 are arrangedin one column.

As illustrated in FIG. 8C, the sensor module 101 having the infraredsensor 202 is inclined at an angle (vertex angle) of θ_(z) relative tothe scan rotation axis S1. An infrared detection element x₀ illustratedin FIG. 8C represents, for example, the infrared detection elementlocated at the lower end of the n infrared detection elementsillustrated in FIG. 8B. A vertex angle between the scan rotation axis S1and a main light ray at a lowest end that is included in the effectiveviewing angle (angle of view) of the infrared detection element x₀ andthat is the closest to the bottom surface 42 is denoted as an angleθ_(x0). In this case, the relationship of angleθ_(x0)=90−FOV/2−θ_(z)−(FOV/2n) holds.

Similarly, for example, an angle θ_(x2) between the scan rotation axisS1 and a main light ray at a lowest end that is included in theeffective viewing angle (angle of view) of an infrared detection elementx₁ adjacent (next) to the infrared detection element x₀ located at thebottom end of the n infrared detection elements and that is the closestto the bottom surface 42 has the following relationship. That is, therelationship of angle θ_(x1)=90-FOV/2−θ_(z)—(FOV/2n)+1*(FOV/n) holds.

Similarly, an angle θ_(x2) between the scan rotation axis S1 and a mainlight ray at a lowest end that is included in the effective viewingangle (angle of view) of the infrared detection element x₂ adjacent(next) to the infrared detection element x₁ and that is the closest tothe bottom surface 42 can be expressed as90-FOV/2-θ_(z)−(FOV/2n)+2*(FOV/n). An angle θ_(xm) between the scanrotation axis S1 and a main light ray at a lowest end that is includedin the effective viewing angle (angle of view) of the mth infrareddetection element x_(m) from the infrared detection element x₀ and thatis the closest to the bottom surface 42 can be expressed as90-FOV/2-θ_(z)−(FOV/2n)+m*(FOV/n).

FIG. 8D conceptually illustrates adjacent infrared detection elements.

The horizontal dimensions of the infrared detection elements satisfy therelationship given by:L _(m+1) /L _(m+2)=sin(θ_(m))/sin(θ_(m+1))  (equation 1)where L_(m) represents the horizontal dimension of the mth infrareddetection element x_(m) from the infrared detection element at thebottom end of the n infrared detection elements, and L_(m+1) representsthe horizontal dimension of the infrared detection element x_(m+1) thatis adjacent to the infrared detection element x_(m) at a side away fromthe bottom surface 42.

When this is generalized, the dimensions of the horizontal edges of theinfrared detection elements satisfy the relationship given by:L _(x) /L _(y)=sin(θ_(x))/sin(θ_(y)),where L_(x) represents the dimension of the horizontal edge of aparticular one of the infrared detection elements in each column, L_(y)represents the dimension of the horizontal edge of the infrareddetection element that is adjacent to the particular infrared detectionelement at the bottom surface 42 side, θ_(x) represents the anglebetween the scan rotation axis S1 and a main light ray at a lowest endthat is included in the angle of view of the particular infrareddetection element and that is the closest to the bottom surface 42, andθ_(y) represents the angle between the scan rotation axis S1 and a mainlight ray at a lowest end that is included in the angle of view of theadjacent infrared detection element.

Forming a plurality of infrared detection elements constituting theinfrared sensor 202 that satisfies the above-noted relationship allowsthe scan densities (resolutions) from the upper end to the lower end tobe equal to each other even when the infrared detection elements in eachrow have a difference in the rotational speeds.

This can eliminate the need for the control processor 12 to perform thedistortion correction as described above in the first embodiment. Thatis, since the control processor 12 does not need to perform thedistortion correction, there are advantages in that the amount of memoryused and the amount of computational load become zero.

The infrared detection elements constituting the infrared sensor 202 arenot limited to those illustrated in FIG. 7 and may be infrared detectionelements as illustrated in FIG. 9. FIG. 9 is a diagram illustratinganother example of the configuration of the infrared sensor in thesecond embodiment.

An infrared sensor 202 b illustrated in FIG. 9 has a plurality ofinfrared detection elements arranged in a plurality of columns is formedsuch that the horizontal edge of each of the infrared detection elementsin each column, the horizontal edge being generally parallel to thebottom surface 42, has a smaller dimension as the infrared detectionelement is located closer to the bottom surface 42. More specifically,in the infrared sensor 202 b illustrated in FIG. 9, infrared detectionelements are arranged in three or more columns; the horizontal edge ofeach of the infrared detection elements in each column, the horizontaledge being generally parallel to the bottom surface 42, has a smallerdimension as the infrared detection element is located closer to thebottom surface 42; and the distance between the central positions of theinfrared detection elements at corresponding positions in the adjacentcolumns of the three or more columns is constant. Since the relationshipof the dimensions of the horizontal edges of the adjacent infrareddetection elements in each column is substantially the same as thatdescribed above, a descriptions thereof is not given hereinafter.

Advantages, Etc. of Second Embodiment

As described above, the infrared detecting device in the presentembodiment includes the infrared sensor 202 whose central axis of thefield of view is inclined relative to the scan rotation axis S1. Thiscan increase the detection range in the area near and below the positionwhere the infrared detecting device is disposed.

Also, the infrared detecting device in the present embodiment has theinfrared sensor 202 formed such that, the closer to the bottom surface42, the smaller the dimension of the horizontal edges of the infrareddetection elements in each column. Thus, even when the rotational speedsof the infrared detection elements in each row in the infrared sensor202 whose central axis of the field of view is inclined relative to thescan rotation axis S1 are different from each other, the scan densities(resolutions) from the upper end to the lower end can be made equal toeach other, there is an advantage in that the distortion correction onthe thermal image is not necessary.

The infrared detection elements constituting the infrared sensor in thepresent embodiment are not limited to the cases illustrated in FIGS. 7and 9, and other examples are described below as modifications.

First Modification

FIG. 10 is a diagram illustrating one example of the configuration of aninfrared sensor in a first modification of the second embodiment.

Although a case in which the spacing of the adjacent columns, that is,the gap between the centers of the infrared detection elements in theadjacent columns, is constant has been described above in the infraredsensor 202 b illustrated in FIG. 9, the present disclosure is notlimited thereto. As in an infrared sensor 202 c illustrated in FIG. 10,the corresponding infrared detection elements in the adjacent columnsmay be formed such that, the closer to the bottom surface 42 theinfrared detection elements are, the smaller the gap between the centersof the infrared detection elements is. That is, in the infrared sensor202 c illustrated in FIG. 10, the infrared detection elements may bearranged in three or more columns; the horizontal edge of each of theinfrared detection elements in each of the column, the horizontal edgebeing generally parallel to the bottom surface 42, may have a smallerdimension as the infrared detection element is located closer to thebottom surface 42; and each of the infrared detection elements in eachof the three or more columns may be located closer to a center of thethree or more columns in a column direction (i.e., in a directionparallel to the scan axis) as the infrared detection element is locatedcloser to the bottom surface 42. Since the relationship of thedimensions of the horizontal edges of the adjacent infrared detectionelements in each column is substantially the same as that illustrated inFIG. 7, a description thereof is not given hereinafter.

With the arrangement described above, since the infrared sensor 202 c inFIG. 10 allows the spacing of the adjacent columns (i.e., the gapbetween the corresponding infrared detection elements in the adjacentcolumns) to be reduced compared with the infrared sensor 202 billustrated in FIG. 9, it is possible to increase the scan density. Thatis, the infrared sensor 202 c in FIG. 10 offers an advantage in that thescanning can be performed with high sensitivity, compared with theinfrared sensor 202 b illustrated in FIG. 9.

Second Modification

FIG. 11A is a diagram illustrating one example of the configuration ofan infrared sensor in a second modification of the second embodiment.FIG. 11B is a diagram illustrating another example of the configurationof the infrared sensor in the second modification of the secondembodiment.

Although a case in which each of the infrared detection elementsconstituting the infrared sensor 202 b illustrated in FIG. 9 has arectangle shape has been described above, the infrared sensor 202 b isnot limited thereto. That is, as in an infrared sensor 202 d asillustrated in FIG. 11A, each of the infrared detection elementsconstituting it may have a parallelogram shape. In addition, althoughthe gap between the corresponding infrared detection elements in theadjacent columns in the infrared sensor 202 d is constant, it may beformed such that, the closer to the bottom surface 42 the infrareddetection elements are, the smaller the gap between the centers of theinfrared detection elements in the adjacent columns is, as illustratedin FIG. 11A.

Thus, since the infrared sensor 202 d in FIG. 11A allows the spacing ofthe adjacent columns (the gaps between the corresponding infrareddetection elements in the adjacent columns) to be reduced compared withthe infrared sensor 202 c illustrated in FIG. 10, it is possible toincrease the scan density. That is, the infrared sensor 202 d in FIG.11A offers an advantage in that the scanning can be performed with highsensitivity, compared with the infrared sensor 202 c illustrated in FIG.10.

Two opposite ends (in FIGS. 11A and 11B, left and right ends) in therotation direction of the infrared detection elements constituting theinfrared sensor 202 d illustrated in FIG. 11A may be disabled, as in aninfrared sensor 202 e illustrated in FIG. 11B. This can suppressinfluences of comatic aberration and spherical aberration of a lens usedfor focusing infrared rays on the infrared sensor. The “sphericalaberration” as used herein refers to aberration resulting from the lenssurface being spherical, that is, resulting from differences in howlight travels between the center portion and peripheral portions of thelens, the differences being caused by the lens surface being spherical.The “comatic aberration” refers to a phenomenon in which a point imagehas a tail at a portion away from the optical axis, that is, aphenomenon in which light that goes out from one point at portion awayfrom the optical axis does not concentrate at one point on an imageplane, an image like a comet having a tail is formed, and the pointimage extends.

Third Modification

FIG. 12A is a diagram illustrating one example of the configuration ofan infrared sensor in a third modification of the second embodiment.FIG. 12B is a diagram illustrating another example of the configurationof the infrared sensor in the third modification of the secondembodiment.

Although the description of the infrared sensor 202 d illustrated inFIG. 11A has been given of a case in which the infrared detectionelements in each column are formed generally parallel to the scanrotation axis S1, and the infrared detection elements in each row areformed generally orthogonal to the scan rotation axis S1, the presentdisclosure is not limited thereto.

As illustrated in FIG. 12A, infrared detection elements constituting aninfrared sensor 202 f and arranged in a matrix may be inclined at apredetermined angle relative to the scan rotation axis S1. Thepredetermined angle in this case is an angle adjusted such that all ofthe respective central positions of the infrared detection elementsconstituting the infrared sensor 202 differ from one another, whenviewed from the direction orthogonal to the scan rotation axis S1.

Thus, when the infrared sensor 202 f is rotated about the scan rotationaxis S1, the number of infrared detection elements in the directionorthogonal to the scan rotation axis S1 increases, compared with a casein which the predetermined angle is not given relative to the scanrotation axis S1. That is, the infrared sensor 202 f in which theinfrared detection elements are inclined at the predetermined anglerelative to the scan rotation axis S1 makes it possible to substantiallyincrease the number of pixels in the direction orthogonal to the scanrotation axis S1. This makes it possible to enhance the resolution inthe direction orthogonal to the scan rotation axis S1.

Two opposite ends (in FIG. 12A, left and right ends) in the rotationdirection of the infrared detection elements constituting the infraredsensor 202 f may be disabled, as in the infrared sensor 202 eillustrated in FIG. 11B. This makes it possible to suppress influencesof the comatic aberration and the spherical aberration of the lens usedfor focusing infrared rays on the infrared sensor.

In addition, as in an infrared sensor 202 g illustrated in FIG. 12B,particular infrared detection elements (that is, the lower end at aleading end in the rotation direction and the upper end at a trailingend in the rotation direction) of the infrared detection elements in thedisabled columns at the left and right ends may be enabled. This isbecause the particular infrared detection elements are located atpositions where the influences of lens distortion can also be reduced.When the particular infrared detection elements (that is, the lower endat the leading end in the rotation direction and the upper end at thetrailing end in the rotation direction) are enabled to increase thenumber of infrared detection elements in the direction (vertical axis)orthogonal to the scan rotation axis S1, the number of pixels of athermal image in the direction orthogonal to the scan rotation axis S1can be increased, compared with a case in which all of the columns atthe two opposite ends are disabled.

Fourth Modification

FIG. 13 is a diagram illustrating one example of the configuration of aninfrared sensor 202 h in a fourth modification of the second embodiment.

Although the infrared sensor 202 illustrated in FIG. 7 has beendescribed above in conjunction with a case in which each of the infrareddetection elements constituting the infrared sensor 202 has arectangular shape, the present disclosure is not limited thereto. Eachof the infrared detection elements constituting the infrared sensor 202may be formed to have a trapezoidal shape, as in the infrared sensor 202h illustrated in FIG. 13. In this case, the dimensions of the verticaledges of the infrared detection elements in the infrared sensor 202 hare equal to each other.

Since the relationship of the dimensions of the horizontal edges of theinfrared detection elements in the columns constituting the infraredsensor 202 h is substantially the same as that illustrated in FIG. 7, adescription thereof is not given hereinafter.

Fifth Modification

FIG. 14 is a diagram illustrating one example of the configuration of aninfrared sensor in a fifth modification of the second embodiment. FIG.15 is a diagram illustrating another example of the configuration of theinfrared sensor in the fifth modification of the second embodiment. FIG.16 is a table illustrating one example of the size of infrared detectionelements constituting the infrared sensor in the fifth modification ofthe second embodiment.

A case in which the spacing of the adjacent columns, that is, the gapbetween the centers of the infrared detection elements in the adjacentcolumns, is constant and the positions of the corresponding infrareddetection elements in the adjacent columns are the same has beendescribed above in the infrared sensor 202 b illustrated in FIG. 9, thepresent disclosure is not limited thereto. In addition, the positions ofthe corresponding infrared detection elements in the adjacent ones ofthe columns may be offset, as in an infrared sensor 202 i illustrated inFIG. 14.

FIG. 14 illustrates an example in which an infrared detection elementg₁₁ at the upper end in a first column and an infrared detection elementg₂₁ at the upper end in a second column are offset by a ¼ pixel, aninfrared detection element g₂₁ at the upper end in the second column andan infrared detection element g₃₁ at the upper end in a third column areoffset by a quarter pixel, and the infrared detection element g₃₁ at theupper end in third column and an infrared detection element g₄₁ at theupper end in a fourth column are offset by a quarter pixel. Similarly,the positions of the corresponding infrared detection elements in theadjacent columns in each row other than the upper end are offset by a ¼pixel.

In other words, in the infrared sensor 202 i illustrated in FIG. 14, thepositions of topmost infrared detection elements in three or morecolumns, viewed from the bottom surface 42, are sequentially offsettoward the bottom surface 42. For example, the position of the topmostinfrared detection element in one column may be offset from the topmostinfrared detection element in the column adjacent thereto by one-fourthof the dimension of the vertical edge of the topmost infrared detectionelement in the adjacent column, the vertical edge being generallyorthogonal to the bottom surface 42. Since the relationship of thedimensions of the horizontal edges of the adjacent infrared detectionelements in each column is substantially the same as that illustrated inFIG. 7, a description thereof is not given hereinafter.

With the configuration described above, when the infrared sensor 202 iis rotated about the scan rotation axis S1, the number of infrareddetection elements in the direction orthogonal to the scan rotation axisS1 increases, compared with the infrared sensor 202 b illustrated inFIG. 9. That is, the infrared sensor 202 i makes it possible tosubstantially increase the number of pixels in the direction orthogonalto the scan rotation axis S1. This makes it possible to enhance theresolution in the direction orthogonal to the scan rotation axis S1.

Although a case in which the spacing of the adjacent columns, that is,the gap between the centers of the infrared detection elements in theadjacent columns, is constant has been described above in the infraredsensor 202 i illustrated in FIG. 14, the present disclosure is notlimited thereto. In addition, the infrared sensor may be formed suchthat, the closer to the bottom surface 42 the corresponding infrareddetection elements in the adjacent ones of the columns are, the smallerthe distance between the centers of the infrared detection elements is,as in an infrared sensor 202 j illustrated in FIG. 15.

FIG. 16 illustrates the dimensions (horizontal dimensions) of thehorizontal edges of the infrared detection elements in each row whichsatisfy equation 1 noted above, when the infrared detection elementsconstituting the infrared sensor in FIGS. 14 and 15 are arranged in 16rows and 4 columns, and a vertex angle θ_(z) relative to the scanrotation axis S1 is 30°.

The dimension (vertical dimension) of a vertical edge may be such thatthe ratio of the dimension of the vertical edge to the dimension of thehorizontal edge of the bottom-end infrared detection element at thelowest end is 2/1, as illustrated in vertical dimension example 1illustrated in FIG. 16. However, when there is a constraint in aprocess, the ratio of the vertical edge to the horizontal edge of theinfrared detection element at the lowest end may be 3/2 (0.75/0.5), asin vertical dimension example 2 illustrated in FIG. 16.

Third Embodiment

Although the infrared detecting device having the infrared sensor whosecentral axis of the field of view is inclined relative to the scanrotation axis parallel to the installation surface 41 has been describedabove in each of the first and second embodiments, the presentdisclosure is not limited thereto. An example of such a case will bedescribed below.

[Configuration of Infrared Detecting Device]

An infrared detecting device in a third embodiment will be describedbelow with reference to the accompanying drawings.

FIG. 17 is a schematic view of a physical configuration when an infrareddetecting device in the third embodiment is attached to the housing.Elements that are the same as or similar to those in FIGS. 1 to 4 aredenoted by the same reference numerals, and detailed descriptionsthereof are not given hereinafter.

The infrared detecting device in the present embodiment is attached tothe housing 2 installed on the installation surface 41 that is generallyorthogonal to the bottom surface 42 of the space 4 and that is locatedat a predetermined height from the bottom surface 42, as illustrated inFIG. 17, to acquire a thermal image in a detection range. Thepredetermined height in this case refers to, for example, a height thatis larger than temperature detection targets (measurement targets), suchas people or heat sources, as in the first and second embodiments, andis, for example, 1800 mm.

In the infrared detecting device in the present embodiment illustratedin FIG. 17, a scan rotation axis S3 of a scanner (a motor 311), a mountbase 312, a sensor module 301, and an infrared sensor 302 are arrangedso as to have an inclination relative to the installation surface 41,unlike the infrared detecting device 1 in the first embodiment. Exceptfor the arrangement, the configuration of the mount base 312, the sensormodule 301, and the infrared sensor 302 is substantially the same as theconfiguration of the mount base 112, the sensor module 101, and theinfrared sensor 102 in the first embodiment, and thus descriptionsthereof are not given hereinafter.

In the present embodiment, the scan rotation axis S3 and the arrangementplane of the infrared sensor 302 are disposed so as to have aninclination relative to the installation surface 41. Thus, a centralaxis C3 of the field of view of the infrared sensor 302 is not parallelto the direction orthogonal to the installation surface 41 (i.e., is notparallel to the bottom surface 42), as illustrated in FIG. 17. The scanrotation axis S3 passes along the arrangement plane of the infraredsensor 302, as illustrated in FIG. 17, and the infrared sensor 302 isrotated about the scan rotation axis S3 that passes along thearrangement plane.

Thus, in the present embodiment, the scan rotation axis S3 is inclinedrelative to the installation surface 41, and the central axis C3 of thefield of view of the infrared sensor 302 is generally orthogonal to thescan rotation axis S3.

Advantages, Etc. of Third Embodiment

With this arrangement, when the infrared sensor 302 is rotated about thescan rotation axis S3, the rotational speed (rotational pitch) of anupper end and a lower end of the infrared sensor 302, when viewed fromthe bottom surface 42, become equal to each other, and thus it is notnecessary for the control processor 12 to perform distortion correctionas described in the first embodiment. That is, since the controlprocessor 12 does not need to perform distortion correction, there is anadvantage in that the amount of memory used and the amount ofcomputational load become zero.

The infrared detecting device in the present embodiment includes theinfrared sensor 302 whose central axis C3 of the field of view isinclined from the direction generally orthogonal to the installationsurface 41 toward the bottom surface 42. This offers an advantage inthat it is possible to increase a detection range in an area near andbelow the position where the infrared detecting device is disposed.

Modifications of First to Third Embodiments

In the second embodiment, the infrared sensor has a plurality ofinfrared detection elements in one or more columns and is formed suchthat the horizontal edge of each of the infrared detection elements ineach column, the horizontal edge being generally parallel to the bottomsurface 42, has a smaller dimension as the infrared detection element islocated closer to the bottom surface 42. The dimensions of thehorizontal edges of the adjacent infrared detection elements in eachcolumn are described above as being defined by equation 1 noted above.However, the dimensions of the horizontal edges are not limited to acase in which they are defined by equation 1.

That is, for example, the dimensions of the horizontal edges are notlimited to a case that satisfies a relationshipL_(x)/L_(y)=sin(θ_(x))/sin(θ_(y)) in equation 1 noted above and maysatisfy a relationship L_(x)/L_(y)>sin(θ_(x))/sin(θ_(y)) or arelationship L_(x)/L_(y)<sin(θ_(x))/sin(θ_(y)).

More specifically, the relationship given byL_(x)/L_(y)>sin(θ_(x))/sin(θ_(y)) may be satisfied, where L_(x)represents the dimension of the horizontal edge of a particular one ofthe infrared detection elements in each column, L_(y) represents thedimension of the horizontal edge of the infrared detection element thatis adjacent to the particular infrared detection element at the bottomsurface 42 side, θ_(x) represents the angle between the scan rotationaxis S1 and a main light ray at a lowest end that is included in theangle of view of the particular infrared detection element and that isthe closest to the bottom surface 42, and θ_(y) represents the anglebetween the scan rotation axis S1 and a main light ray at a lowest endthat is included in the angle of view of the adjacent infrared detectionelement.

In this case, there is an advantage in that, of the infrared detectionelements constituting the infrared sensor, the infrared detectionelements whose effective viewing angles are horizontal (i.e., parallelto the bottom surface 42) can perform scanning with higher sensitivity.This is suitable for a case in which it is desired to scan, with highsensitivity, a measurement target that is horizontally far from theposition where the infrared detecting device is disposed.

Also, the relationship given by L_(x)/L_(y)<sin(θ_(x))/sin(θ_(y)) may besatisfied, where L_(x) represents the dimension of the horizontal edgeof a particular one of the infrared detection elements in each column,L_(y) represents the dimension of the horizontal edge of the infrareddetection element that is adjacent to the particular infrared detectionelement at the bottom surface 42 side, θ_(x) represents the anglebetween the scan rotation axis S1 and a main light ray at a lowest endthat is included in the angle of view of the particular infrareddetection element and that is the closest to the bottom surface 42, andθ_(y) represents the angle between the scan rotation axis S1 and a mainlight ray at a lowest end that is included in the angle of view of theadjacent infrared detection element.

In this case, there is an advantage in that scanning can be performedwith a higher scan density (with higher sensitivity) relative to adistance for the infrared detection element that is closer to theposition directly below the position where the infrared detecting deviceis disposed. This is suitable for a case in which it is desired to scan,with high sensitivity, the area directly below the position where theinfrared detecting device is disposed.

The housing to which the infrared detecting device described above ineach of the first to third embodiments is attached is not limited to thehousing of air-conditioning equipment. The infrared detecting device maybe attached to a security camera or a microwave oven.

Advantages, Etc. of First to Third Embodiments

An infrared detecting device according to one aspect of the presentdisclosure is directed to an infrared detecting device attached to ahousing installed on an installation surface that is generallyorthogonal to a bottom surface of space and that is located at apredetermined height from the bottom surface. The infrared detectingdevice includes an infrared sensor having one or more infrared detectionelements arranged in one or more columns and a scanner that has a scanrotation axis and that rotates the infrared sensor about the scanrotation axis to cause the infrared sensor to scan the space. Anarrangement plane of the one or more infrared detection elements isarranged so as to have an inclination relative to the installationsurface.

With this configuration, it is possible to realize an infrared detectingdevice that can increase a detection range in an area near and below theposition where the infrared detecting device is disposed.

In this case, for example, the center of the arrangement plane may havea rotation center through which the scan rotation axis passes, that is,a rotation center when the infrared sensor is rotated about the scanrotation axis.

In addition, for example, the scan rotation axis and the arrangementplane may be arranged so as to have the inclination relative to theinstallation surface, the scan rotation axis may pass along thearrangement plane, and the infrared sensor may be rotated about the scanrotation axis that passes along the arrangement plane.

For example, the scan rotation axis may be generally parallel to theinstallation surface, and the arrangement plane may intersect the scanrotation axis.

In this case, for example, the infrared detection elements in theinfrared sensor are arranged in one or more columns; and a horizontaledge of each of the infrared detection elements in each column, thehorizontal edge being generally parallel to the bottom surface, has asmaller dimension, as the infrared detection element is located closerto the bottom surface.

In addition, for example, the relationship given byL_(x)/L_(y)=sin(θ_(x))/sin(θ_(y)) may be satisfied, where L_(x)represents the dimension of the horizontal edge of a particular one ofthe infrared detection elements in each column, L_(y) represents thedimension of the horizontal edge of the infrared detection element thatis adjacent to the particular infrared detection element at the bottomsurface 42 side, θ_(x) represents the angle between the scan rotationaxis S1 and a main light ray at a lowest end that is included in theangle of view of the particular infrared detection element and that isthe closest to the bottom surface 42, and θ_(y) represents the anglebetween the scan rotation axis S1 and a main light ray at a lowest endthat is included in the angle of view of the adjacent infrared detectionelement.

Also, for example, the relationship given byL_(x)/L_(y)>sin(θ_(x))/sin(θ_(y)) may be satisfied, where L_(x)represents the dimension of the horizontal edge of a particular one ofthe infrared detection elements in each column, L_(y) represents thedimension of the horizontal edge of the infrared detection element thatis adjacent to the particular infrared detection element at the bottomsurface 42 side, θ_(x) represents the angle between the scan rotationaxis S1 and a main light ray at a lowest end that is included in theangle of view of the particular infrared detection element and that isthe closest to the bottom surface 42, and θ_(y) represents the anglebetween the scan rotation axis S1 and a main light ray at a lowest endthat is included in the angle of view of the adjacent infrared detectionelement.

Also, for example, the relationship given byL_(x)/L_(y)<sin(θ_(x))/sin(θ_(y)) may be satisfied, where L_(x)represents the dimension of the horizontal edge of a particular one ofthe infrared detection elements in each column, L_(y) represents thedimension of the horizontal edge of the infrared detection element thatis adjacent to the particular infrared detection element at the bottomsurface 42 side, θ_(x) represents the angle between the scan rotationaxis S1 and a main light ray at a lowest end that is included in theangle of view of the particular infrared detection element and that isthe closest to the bottom surface 42, and θ_(y) represents the anglebetween the scan rotation axis S1 and a main light ray at a lowest endthat is included in the angle of view of the adjacent infrared detectionelement.

For example, the infrared detection elements in the infrared sensor maybe arranged in three or more columns; a horizontal edge of each of theinfrared detection elements in each column, the horizontal edge beinggenerally parallel to the bottom surface, may have a smaller dimension,as the infrared detection element is located closer to the bottomsurface; and a distance between central positions of the infrareddetection elements at corresponding portions in the adjacent columns ofthe three or more columns may be constant.

For example, the infrared detection elements in the infrared sensor maybe arranged in three or more columns; the horizontal edge of each of theinfrared detection elements in each of the column, the horizontal edgebeing generally parallel to the bottom surface, may have a smallerdimension, as the infrared detection element is located closer to thebottom surface; and each of the infrared detection elements in each ofthe three or more columns may be located closer to a center of the threeor more columns in a column direction, as the infrared detection elementis located closer to the bottom surface.

For example, positions of the topmost infrared detection elements in thethree or more columns, viewed from the bottom surface, may besequentially offset toward the bottom surface.

For example, the position of the topmost infrared detection element inone column may be offset from the topmost infrared detection element inthe column adjacent thereto by one-fourth of a dimension of a verticaledge of the topmost infrared detection element in the adjacent column,the vertical edge being generally orthogonal to the bottom surface.

For example, in the infrared sensor, the one or more columns may bearranged so as to have an inclination at a predetermined angle relativeto the scan rotation axis.

For example, the predetermined angle may be an angle adjusted such thatall of the respective central positions of the infrared detectionelements constituting the infrared sensor differ from one another, whenviewed from a direction orthogonal to the scan rotation axis.

General or specific aspects may be implemented as a system, a method, anintegrated circuit, a computer program, a storage medium such as acomputer-readable compact disc read-only memory (CD-ROM), or anyselective combination thereof.

Fourth Embodiment

In a fourth embodiment, a description will be given of a specific aspectof an infrared detecting device that can enhance the resolution of athermal image without increasing the number of infrared detectionelements.

[Configuration of Infrared Detecting Device]

The infrared detecting device in the fourth embodiment will be describedbelow with reference to the accompanying drawings.

FIG. 18 is a diagram illustrating one example of the configuration of aninfrared detecting device 1A in the fourth embodiment. FIG. 19A is adiagram illustrating one example of the configuration of an infrareddetector 10 and a scanner 11 in the present embodiment. FIG. 19B is adiagram illustrating one example of the configuration of an infraredsensor 102A in the present embodiment.

As illustrated in FIG. 18, the infrared detecting device 1A includes aninfrared detector 10, a scanner 11, and a control processor 12.

The scanner 11 causes the infrared detector 10 to perform scanning in apredetermined direction. More specifically, by moving the infraredsensor 102A in a predetermined direction, the scanner 11 causes theinfrared sensor 102A to scan a detection range. In the presentembodiment, the scanner 11 has a motor 111 illustrated in FIG. 19A.Under the control of the control processor 12, the motor 111 causes theinfrared sensor 102A of a sensor module 101 to rotate or move in apredetermined direction. The motor 111 is, for example, a stepping motoror a servo motor. The predetermined direction is a horizontal directionin FIG. 19A and corresponds to the direction (scan direction) of a scanaxis illustrated in FIG. 19B.

The control processor 12 controls the scanner 11 to process thermalimages (input images) acquired by the infrared detector 10. Asillustrated in FIG. 18, the control processor 12 includes an equipmentcontroller 121 and an image processor 122.

The equipment controller 121 determines control information forcontrolling scanning of the scanner 11 on the basis of informationdetected by the infrared detector 10 and controls the scanner 11 inaccordance with the determined control information. The image processor122 generates a high-definition thermal image (an output image) byperforming super resolution processing on the thermal images (the inputimages) acquired by the infrared detector 10 and recombining the thermalimages (the input images). The image processor 122 outputs the generatedhigh-definition thermal image, that is, the thermal image on which thesuper resolution processing is performed.

The “thermal image” as used herein refers to an image constituted by aplurality of pixels indicating the distribution of temperatures in atemperature detection range. The “super resolution processing” as usedherein is one type of resolution-enhancement processing that cangenerate high-resolution information (an output image) that is notincluded in an input image. A processing method for acquiring a singlehigh-resolution image from a plurality of images and a processing methodusing learning data are available as the super resolution processing. Inthe present embodiment, the scanner 11 causes the infrared detector 10to perform scanning to thereby allow acquisition of a thermal image(with sub-pixel position displacement) of a temperature detection range,that is, thermal-image data of different sample points. Thus, thefollowing description will be given assuming that a processing methodfor obtaining one high-resolution thermal image from a plurality ofthermal images.

In addition, the image processor 122 may obtain thermal-image dataindicating the positions and the temperatures of heat sources in thetemperature detection range on the basis of the thermal image on whichthe super resolution processing is performed, and then may output thethermal-image data. Examples of the positions and the temperatures ofthe heat sources include the positions of people, the temperatures of auser's hand and face, and the temperatures of walls.

The scanner 11 causes the infrared detector 10 to perform scanning in apredetermined direction to thereby allow the infrared detector 10 toacquire a thermal image of a temperature detection range. Morespecifically, the infrared detector 10 has the infrared sensor 102A inwhich a plurality of infrared detection elements are arranged in amatrix, and detects infrared rays in a temperature detection rangescanned by the infrared sensor 102A. The infrared sensor 102A isdisposed so that the matrix of the infrared detection elements has aninclination at a predetermined angle relative to the predetermineddirection. The “predetermined angle” in this case refers to an angleadjusted such that all of the respective central positions of theinfrared detection elements constituting the infrared sensor 102A differfrom one another, when viewed from the predetermined direction.

In the present embodiment, the infrared detector 10 includes, forexample, the sensor module 101 illustrated in FIG. 19A. The sensormodule 101 has the infrared sensor 102A and a lens (not illustrated).

The lens is made of silicon, zinc sulfide (ZnS), or the like having ahigh infrared transmittance. The lens is designed so that infrared rays(infrared light) that enter the lens from individual directions areincident on the different infrared detection elements constituting theinfrared sensor 102A.

The infrared detection elements constituting the infrared sensor 102Aare arranged, for example, in a matrix with N rows and M columns (N andM are natural numbers greater than or equal to 2), as illustrated inFIG. 19B. Also, upon being rotated (moved) in the horizontal direction,that is, along the direction of the scan axis illustrated in FIG. 19B,the infrared sensor 102A can scan a temperature detection range. Whenthe scanning is performed in the predetermined direction (the horizontaldirection), the infrared detector 10 acquires a thermal image (aninfrared thermal image) of the temperature detection range and outputsthe thermal image to the image processor 122.

More specifically, the motor 111 rotates (moves) the infrared sensor102A for each sub-pixel position in the horizontal direction, that is,in the direction of the scan axis illustrated in FIG. 19B. As a result,the infrared sensor 102A acquires a thermal image (an infrared thermalimage) of the temperature detection range, the thermal image havingsub-pixel position displacement, and outputs the thermal image to theimage processor 122.

The infrared sensor 102A is inclined at a predetermined angle (X in FIG.19B) relative to the horizontal direction, that is, the direction of thescan axis illustrated in FIG. 19B. In other words, the infrared sensor102A is constituted by a plurality of infrared detection elementsarranged in a matrix with N rows and M columns, and the infrareddetection elements in the matrix are arranged so as to be parallel andorthogonal to a sensor axis having an inclination at a predeterminedangle (X) relative to the scan axis. That is, the predetermined angle(X) is an angle adjusted such that all of the respective centralpositions of the infrared detection elements constituting the infraredsensor 102A differ from one another, when viewed from the direction ofthe scan axis. In addition, in other words, the predetermined angle (X)is an angle adjusted such that, when the infrared detection elements arerotated (moved) along the direction of the scan axis, the infrareddetection elements in the M columns in one row parallel to the sensoraxis and the infrared detection elements in the row adjacent thereto donot overlap each other in the direction of the scan axis.

Since the infrared sensor 102A is inclined at the predetermined angle (Xin FIG. 19B) relative to the direction of the scan axis, the infrareddetection elements constituting the infrared sensor 102A have thefollowing relationships. That is, the distances (e.g., first distances)in the direction orthogonal to the scan axis (in FIG. 19B, in thevertical direction) between the respective central positions of theinfrared detection elements that are adjacent in the same row (e.g., ina first arrangement) are equal to each other. Also, the distance (e.g.,a second distance) in the direction orthogonal to the scan axis (i.e.,in the vertical direction) between the central position of the infrareddetection element (e.g., a first element) that is located at one end ofthat row (the first arrangement), the end corresponding to a leading endin the scan direction, and the central position of the infrareddetection element (e.g., a second element) that is included in the row(e.g., a second arrangement) adjacent to that row (the firstarrangement) and that is adjacent to the infrared detection element atanother end of that row (the first arrangement) is equal to the firstdistance.

With this arrangement, when the infrared detection elements are rotated(moved) along the direction of the scan axis, the number of infrareddetection elements in the direction orthogonal to the scan axis becomeslarger than N when the scan axis and the sensor axis are parallel toeach other. That is, the infrared sensor 102A whose sensor axis isinclined at the predetermined angle (X) relative to the scan axis cansubstantially increase the number of pixels of a thermal image in thedirection (the vertical axis direction) orthogonal to the scan axis,compared with a case in which the sensor axis is parallel to the scanaxis. This makes it possible to enhance the resolution in the direction(the vertical axis direction) orthogonal to the scan axis.

One example of the predetermined angle will be described below inconjunction with an illustrative example.

Illustrative Example

Next, one example of the configuration of the infrared sensor 102A in anillustrative example will be described with reference to FIGS. 20 and21.

FIG. 20 is a diagram illustrating an infrared sensor in an illustrativeexample of the fourth embodiment.

An infrared sensor 102 a illustrated in FIG. 20 is one example of theinfrared sensor 102A and is constituted by a plurality of infrareddetection elements arranged in 8 rows and 8 columns. Detection pointsare depicted at the respective centers of the infrared detectionelements illustrated in FIG. 20. The infrared detecting sensitivity ofthe detection points of the infrared detection elements may be high, andthe detection points may detect infrared rays. While the entire area ofthe infrared detection element detects infrared rays, the detectionpoint of each infrared detection element may dominantly detect infraredrays. The detection point may also represent the area of thecorresponding infrared detection element. In this case, the detectionpoint may represent the average of infrared rays detected by thecorresponding infrared detection element.

The sensor axis of infrared detection elements in the 8 rows and 8columns constituting the infrared sensor 102 a is inclined at apredetermined angle a relative to a horizontal direction, that is, thedirection of a scan axis illustrated in FIG. 20. The predetermined anglea is one example of the above-described predetermined angle x, and isadjusted such that all of the central positions of the infrareddetection elements in the 8 rows and 8 columns differ from one another,when viewed from the direction of the scan axis. In other words, thepredetermined angle a is adjusted such that, when the infrared detectionelements constituting the infrared sensor 102 a and arranged in the 8×8matrix are rotated (moved) along the direction of the scan axis, theinfrared detection elements in 8 columns in one row parallel to thesensor axis and the infrared detection elements in 8 columns in the rowadjacent thereto do not overlap each other in the direction of the scanaxis.

FIG. 21 is a diagram for describing the inclination of the infraredsensor 102 a illustrated in FIG. 20. For convenience of description,FIG. 21 illustrates infrared detection elements in two rows of theinfrared detection elements arranged in the 8 rows and 8 columnsillustrated in FIG. 20. In FIG. 21, dotted lines S₁ and S₂ are parallelto the scan axis.

In FIG. 21, the predetermined angle a is an angle adjusted such thatinfrared detection elements a₁₁ to a₁₈ and infrared detection elementsa₂₁ to a₂₈ do not overlap each other in the direction of the scan axiswhen they are rotated (moved) along the direction of the scan axis.

For example, a distance h in a vertical direction between the respectivecentral positions of the infrared detection elements a₁₁ and a₁₂, adistance h in the vertical direction between the respective centralpositions of the infrared detection elements a₁₂ and a₁₃, a distance hin the vertical direction between the respective central positions ofthe infrared detection elements a₁₃ and a₁₄, a distance h in thevertical direction between the respective central positions of theinfrared detection elements a₁₄ and a₁₅, a distance h in the verticaldirection between the respective central positions of the infrareddetection elements a₁₅ and a₁₆, a distance h in the vertical directionbetween the respective central positions of the infrared detectionelements a₁₆ and a₁₇, and a distance h in the vertical direction betweenthe respective central positions of the infrared detection elements a₁₇and a₁₈ are all equal to the first distance. This is also true for thecase of the infrared detection elements a₂₁ to a₂₈.

The second distance, that is, a distance h in the vertical directionbetween the respective central positions of the infrared detectionelement a₁₈ (a first element) and the infrared detection element a₂₁ (asecond element) is equal to the first distance. The distance in thevertical direction between the respective central positions of theinfrared detection elements a₁₁ and a₁₈ is 8h.

Thus, the predetermined angle a that satisfies the above-describedrelationship is an angle that satisfies tan⁻¹ (⅛) and can be determinedto be 7.125°.

That is, the infrared sensor 102 a is constituted by the 8×8 infrareddetection elements that are parallel and orthogonal to the sensor axis,and the sensor axis has an inclination (the predetermined angle a) of7.125° relative to the scan axis. Thus, all of the central positions ofthe infrared detection elements constituting the infrared sensor 102 aand arranged in the 8 rows and 8 columns differ from one another, whenviewed from the direction of the scan axis. As described above, sinceall of the infrared detection elements constituting the infrared sensor102 a and arranged in the 8 columns can be arranged so as not to overlapeach other in the direction of the scan axis, it is possible tosubstantially increase the number of pixels of a thermal image in thedirection (the vertical axis direction) orthogonal to the scan axis.

Although the infrared detection elements in the 8 rows and 8 columnshave been described in the illustrative example as one example of theinfrared detection elements constituting the infrared sensor 102A andarranged in the N rows and M columns, the present disclosure is notlimited thereto.

For example, the infrared detection elements may be infrared detectionelements in 4 rows and 4 columns, infrared detection elements in 32 rowsand 32 columns, or infrared detection elements in 16 rows and 16columns. This is because infrared detection elements in N rows and Ncolumns (N is a natural number greater than or equal to 2) are availableas off-the-shelf products, and thus it is possible to reduce the cost ofemploying the infrared sensor.

FIG. 22A is a diagram for describing an advantage of the infrareddetecting device when an infrared sensor 502 a in a comparative exampleis used. FIG. 22B is a diagram for describing an advantage of theinfrared detecting device when the infrared sensor 102 a illustrated inFIG. 20 is used.

The infrared sensor 502 a in the comparative example illustrated in FIG.22A is not inclined relative to the direction of the scan axis (i.e.,relative to the horizontal direction). That is, the sensor axis of theinfrared sensor 502 a matches the scan axis. In this case, when 8×8infrared detection elements constituting the infrared sensor 502 a arerotated (moved) along the direction of the scan axis, the infrareddetection elements in the direction (column direction) parallel to thescan axis overlap each other. Thus, the number of infrared detectionelements in the direction orthogonal to the scan axis remains to beeight.

On the other hand, the infrared sensor 102 a illustrated in FIG. 22B isinclined at 7.125° relative to the direction of the scan axis (i.e.,relative to the horizontal direction). That is, the sensor axis of theinfrared sensor 102 a is inclined at 7.125° relative to the scan axis.In this case, when the 8×8 infrared detection elements constituting theinfrared sensor 102 a are rotated (moved) along the direction of thescan axis, the infrared detection elements in the direction (columndirection) parallel to the scan axis do not match each other. As aresult, the number of infrared detection elements in the directionorthogonal to the scan axis increases to 64 (64 vertical levels), whichis larger than eight (8 vertical levels), which is the number ofinfrared detection elements in a row direction of the infrared sensor102 a.

Thus, since the infrared detecting device 1A has the infrared sensor 102a constituted by the infrared detection elements whose sensor axis isinclined at an angle of 7.125° relative to the scan axis, it is possibleto acquire a thermal image having a resolution that is eight times ashigh as that in the comparative example, without increasing the numberof infrared detection elements in the infrared sensor 102 a. Inaddition, when the control processor 12 performs super resolutionprocessing on the thermal image, the infrared detecting device 1A canacquire a thermal image having a more enhanced resolution.

[Operation of Infrared Detecting Device]

Next, a description will be given of an operation of the infrareddetecting device 1A configured as described above.

FIG. 23 is a flowchart illustrating an operation of the infrareddetecting device 1A in the fourth embodiment.

First, the infrared detecting device 1A causes the infrared detector 10to perform scanning (S10) to acquire thermal images of a temperaturedetection range (S11). More specifically, by moving (rotating) theinfrared sensor 102 a of the infrared detector 10 along the scan axis,the infrared detecting device 1A causes the infrared sensor 102 a toscan a temperature detection range to acquire thermal images of thetemperature detection range. The scanner 11 moves (rotates) the infraredsensor 102 a for each sub pixel to perform scanning to obtain thermalimages moved for each sub pixel.

Next, the infrared detecting device 1A performs super resolutionprocessing on the acquired thermal images (S12). More specifically, theinfrared detecting device 1 performs processing on the acquired thermalimages and recombines the resulting thermal images to generate a singlehigh-definition thermal image.

Next, the infrared detecting device 1A outputs the generatedhigh-definition thermal image, that is, the thermal image on which thesuper resolution processing is performed (S13).

As described above, the infrared detecting device 1A can acquire, with ahigh resolution, thermal images of a temperature detection range.

[Advantages, Etc. Of Fourth Embodiment]

As described above, the infrared detecting device in the presentembodiment includes the infrared sensor constituted by the infrareddetection elements whose sensor axis is inclined at a predeterminedangle relative to the scan axis. This makes it possible to enhance theresolution of the thermal image, without increasing the number ofinfrared detection elements constituting the infrared sensor. The“predetermined angle” in this case is an angle adjusted such that all ofthe respective central positions of the infrared detection elementsconstituting the infrared sensor are different from one another, whenviewed from a predetermined direction that is the scan direction. Forexample, when the infrared sensor is constituted by infrared detectionelements in 8 rows and 8 columns, the predetermined angle is 7.125°.

Since the infrared detecting device in the present embodiment canacquire a high-resolution thermal image without an increase in thenumber of infrared detection elements constituting the infrared sensor,it is not necessary to additionally install a motor for moving theinfrared sensor (i.e., for causing it scan) in the direction orthogonalto the scan axis. Also, since the infrared detecting device in thepresent embodiment can acquire a high-resolution thermal image withoutan increase in the number of infrared detection elements constitutingthe infrared sensor, it is not necessary to employ a high-cost infraredsensor having a larger number of infrared detection element. That is,the infrared detecting device in the present embodiment offers anadvantage in that it is possible to reduce not only the cost for a motorfor acquiring a high-resolution thermal image but also the cost foremploying an infrared sensor having a larger number of infrareddetection elements.

Also, with the infrared detecting device in the comparative examplewhich can acquire a high-resolution thermal image by additionallyinstalling a motor to increase the number of scan directions of theinfrared sensor, the size of the infrared detecting device increasesmechanically by an amount corresponding to the installed motor. Thismakes it difficult to attach the infrared detecting device in thecomparative example, for example, to other equipment, such asair-conditioning equipment, as a module. On the other hand, since theinfrared detecting device in the present embodiment does not requireadditional installation of a motor for increasing the number of scandirections (scan in the direction orthogonal to the above-described scanaxis), the size does not increase. Accordingly, the infrared detectingdevice in the present embodiment also offers an advantage in that it canbe easily attached, for example, to other equipment, such asair-conditioning equipment, as a module.

In addition, compared with a case in which a motor is additionallyinstalled in order to move the infrared sensor (i.e., to cause it toperform scanning) in the direction orthogonal to the scan axis, theinfrared detecting device in the present embodiment also does notrequire a time for additionally performing scanning in the directionorthogonal to the scan axis after performing scanning in the directionof the scan axis. That is, the infrared detecting device in the presentembodiment also has an advantage in that it is possible to enhance theresolution of thermal images without increasing the infrared detectiontime.

This advantage will be described in detail. Since the infrared detectingdevice in the comparative example can acquire a high-resolution thermalimage by additionally installing a motor to increase the number of scandirections of the infrared sensor, the scanning time (the infrareddetection time) for acquiring a thermal image increases by an amountcorresponding to the increased number of scan directions. That is, sincethe infrared detecting device in the comparative example requires a timefor acquiring a thermal image of a temperature detection range, a timedifference between the start of scan and acquisition of the thermalimage is large, and thus there is a problem in that the resolution ofthe acquired thermal images becomes lower than an expected resolution.On the other hand, since the infrared detecting device in the presentembodiment does not require additional installation of a motor forincreasing the number of scan directions (the number of scans in theorthogonal direction), it is possible to enhance the resolution of athermal image without increasing the infrared detection time.

Modification

Although a case in which all of the infrared detection elementsconstituting the infrared sensor are enabled (i.e., all of the infrareddetection elements constituting the infrared sensor are used) has beendescribed in the fourth embodiment, the present disclosure is notlimited thereto. Considering influences of the comatic aberration andthe spherical aberration of the lens used for focusing infrared rays onthe infrared sensor, the arrangement may be such that particular ones ofthe infrared detection elements constituting the infrared sensor areenabled and the infrared detection elements other than the particularinfrared detection elements are disabled.

An example of such a case will be described below as a modification.

The “spherical aberration” as used herein refers to aberration resultingfrom the lens surface being spherical, that is, resulting fromdifferences in how light travels between the center portion andperipheral portions of the lens, the differences being caused by thelens surface being spherical. The “comatic aberration” refers to aphenomenon in which a point image has a tail at a portion away from theoptical axis, that is, a phenomenon in which light that goes out fromone point at portion away from the optical axis does not concentrate atone point on an image plane, an image like a comet having a tail isformed, and the point image extends.

[Configuration of Infrared Sensor]

FIG. 24 is a diagram illustrating one example of the configuration of aninfrared sensor 102 b in a modification of the fourth embodiment.

The infrared sensor 102 b is one example of the infrared sensor 102A.Infrared detection elements constituting the infrared sensor 102 b arearranged in N rows and N columns (N is a natural number greater than orequal to 2), and the infrared detection elements in the columns at twoopposite ends of the N columns are disabled. That is, the infraredsensor 102 b uses particular infrared detection elements that are theinfrared detection elements in N rows and L columns, except the columnsat two opposite ends of the N columns (L is smaller than N and is anatural number greater than or equal to 2). The reason why the columnsat the two opposite ends of the N columns are excluded is that, thefarther the infrared detection element of the infrared sensor 102 b isfrom the center, the larger the influences of the comatic aberration andthe spherical aberration of the lens used for the infrared sensor 102 bbecome.

The infrared sensor 102 b is also inclined at a predetermined angle (X₁in FIG. 24) relative to the direction of the scan axis, as in the fourthembodiment. The predetermined angle X₁ is an angle adjusted such thatall of the respective central positions of the infrared detectionelements constituting the infrared sensor 102 b and arranged in the Nrows and N columns differ from one another, when viewed from thedirection of the scan axis. For example, when the infrared sensor 102 bis constituted by infrared detection elements in 8 rows and 8 columns,and the particular infrared detection elements are the infrareddetection elements in 8 rows and 6 columns, the predetermined angle X₁is 9.462°.

The predetermined angle may be an angle adjusted such that all of therespective central positions of the infrared detection elements in some(N rows and L columns) of the N rows and N columns, not all of therespective central positions of the infrared detection elementsconstituting the infrared sensor 102 b and arranged in the N rows and Ncolumns, differ from one another, when viewed from the direction of thescan axis. In this case, the central positions of the infrared detectingelements in the N rows and L columns may be spaced at equal intervalswhen viewed from the direction of the scan axis.

In addition, it is desirable that the predetermined angle have a valuethat satisfies the equation:X ₁=arctan(1/C _(eff)),where X₁ represents the predetermined angle, and C_(eff) represents thenumber of columns in which the pixels are used. In this equation,C_(eff) is 6 in the case of FIG. 24. In a case described below andillustrated in FIG. 25, C_(eff) is also 6.

Advantages, Etc. of Modification

As described above, according to the infrared detecting device in thismodification, it is possible to enhance the resolution of a thermalimage without increasing the number of infrared detection elementsconstituting the infrared sensor. In addition, in this modification,some (particular infrared detection elements) of the infrared detectionelements constituting the infrared sensor are used rather than using allof the infrared detection elements. This offers an advantage in that itis possible to reduce the influences of the comatic aberration or thespherical aberration of a lens used for focusing infrared rays on theinfrared sensor.

Although, in this modification, a case in which the infrared detectionelements except some of the infrared detection elements in the columnsat two opposite ends in the direction of the scan axis are enabled andused has been described above as an example in which some of theinfrared detection elements constituting the infrared sensor are used,the present disclosure is not limited thereto. For example, some of theinfrared detection elements in the columns at the two opposite ends inthe direction of the scan axis may also be enabled, as illustrated inFIG. 25.

FIG. 25 is a diagram illustrating one example of the configuration of aninfrared sensor in another example of the modification of the fourthembodiment. Elements that are the same as or similar to those in FIG. 24are denoted by the same reference numerals, and detailed descriptionsthereof are not given hereinafter.

An infrared sensor 102 c illustrated in FIG. 25 is one example of theinfrared sensor 102A and is constituted by infrared detection elementsarranged in N rows and N columns (N is a natural number greater than orequal to 2).

In the infrared sensor 102 c, the infrared detection elements exceptsome of the infrared detection elements in the columns at two oppositeends of the N column are enabled. More specifically, as illustrated inFIG. 25, the infrared sensor 102 c uses the infrared detection elementsin N rows and L columns (L is smaller than N and is a natural numbergreater than or equal to 2) except the columns at two opposite ends ofthe N columns, the infrared detection element at the lower end at theright end (i.e., of the two opposite ends of the N columns, the endcorresponding to the leading end during scanning) in FIG. 25, and theinfrared detection element at the upper end at the left end (of the twoopposite ends of the N columns, the end corresponding to the trailingend during scanning) in FIG. 25. The reason why the columns at the twoopposite ends of the N columns are excluded is that the influences ofthe comatic aberration and the spherical aberration increase, asdescribed above. The reason why some (particular) infrared detectionelements in the columns at the two opposite ends of the N columns areenabled is to increase the number of infrared detection elements in thedirection (vertical axis) orthogonal to the scan axis to therebyincrease the field of view along the vertical axis, in order to increasethe number of pixels of a thermal image in the direction (vertical axis)orthogonal to the scan axis, and also the reason is that the particularinfrared detection elements are located at positions where influences oflens distortion can be reduced.

Fifth Embodiment

An example of a case in which some of all the infrared detectionelements constituting the infrared sensor are enabled is not limited tothe above-described examples. In a fifth embodiment, a description willbe given of another configuration example of the particular infrareddetection elements. Differences from the fourth embodiment will bemainly described below.

[Configuration of Infrared Sensor]

FIG. 26 is a diagram illustrating a configuration example of one exampleof an infrared sensor in the fifth embodiment. FIG. 27 is a diagram fordescribing the inclination of the infrared sensor illustrated in FIG.26.

An infrared sensor 102 d is one example of the infrared sensor 102A.Particular ones of the infrared detection elements constituting theinfrared sensor 102 d are enabled, and the infrared detection elementsother than the particular infrared detection elements are disabled.

In the present embodiment, the infrared detection elements constitutingthe infrared sensor 102 d are arranged in N rows and N columns (N is anatural number greater than or equal to 2), and the particular infrareddetection elements are the infrared detection elements other than theinfrared detection elements at, of the N rows and N columns, twoopposite ends in the direction of the scan axis.

More specifically, the particular infrared detection elementsillustrated in FIG. 26 have a first element column, which includes theinfrared detection elements arranged along a first diagonal line havingthe larger angle relative to the direction of the scan axis of twodiagonal lines of the N rows and N columns, second element columns,which include the infrared detection elements arranged adjacent to thefirst element column and along the first diagonal line, third elementcolumns, which include the infrared detection elements arranged adjacentto the second element columns and along the first diagonal line, andfourth element columns, which include the infrared detection elementsarranged adjacent to the third element columns and along the firstdiagonal line. That is, of the infrared detection elements constitutingthe infrared sensor 102 d, the infrared detection elements in the firstto fourth element columns are enabled as the particular infrareddetection elements, and the other infrared detection elements aredisabled.

The infrared sensor 102 d is also inclined at a predetermined angle (x₂in FIG. 26) relative to the direction of the scan axis, as in the fourthembodiment. The predetermined angle x₂ is an angle adjusted such thatall of the respective central positions of the particular infrareddetection elements differ from one another, when viewed from thedirection of the scan axis.

Now, a method for calculating the predetermined angle x₂ will bedescribed with reference to FIG. 27, which is a partial diagram of anarea F1 illustrated in FIG. 26, by way of example. In FIG. 27, dottedlines S₁₁, S₁₂, and S₁₃ are parallel to the scan axis. A dotted line L₁₁connects infrared detection elements c₁₁, c₁₃, and c₁₅ and is parallelto the sensor axis. Similarly, a dotted line L₁₂ connects infrareddetection elements c₁₂ and c₁₄ and is parallel to the sensor axis. Also,each of the dashed lines L₁₁ and L₁₂ is orthogonal to the first diagonalline. That is, each of the dashed lines L₁₁ and L₁₂ is parallel to asecond diagonal line, which is one of the two diagonal lines of thematrix with N rows and N columns and forms a smaller angle with respectto the direction of the scan axis. The infrared detecting elements c₁₁,c₁₃, and c₁₅ are aligned along a direction parallel to the seconddiagonal line. The infrared detecting elements c₁₂ and c₁₄ are alignedalong the direction parallel to the second diagonal line.

For example, a distance h₂ in a direction (in FIG. 27, the verticaldirection) orthogonal to the scan axis between the respective centralpositions of the infrared detection elements c₁₁ and c₁₃, a distance h₂in the direction (in FIG. 27, the vertical direction) orthogonal to thescan axis between the respective central positions of the infrareddetection elements c₁₃ and c₁₅, and a distance h₂ in the direction (inFIG. 27, the vertical direction) orthogonal to the scan axis between therespective central positions of the infrared detection elements c₁₂ andc₁₄ are all equal to each other. The distance in the direction (in FIG.27, the vertical direction) orthogonal to the scan axis between therespective central positions of the infrared detection elements c₁₁ andc₁₂ is h₂ times of P (i.e., P×h₂), where P is “the number of elementcolumns”−1.

By calculating an angle x₂ that satisfies such a relationship, it ispossible to calculate the predetermined angle x₂. Specifically, such arelationship can be represented as relational expressions:sin(x ₂)=Ph ₂ /D ₁sin(45−x ₂)=h ₂/(√2·D ₁)where D₁ represents the distance between the infrared detection elementsand is, for example, the distance (the distance on the sensor axis)between the central positions of the infrared detection elements c₁₁ andc₁₂.

By solving the relational expressions, it is possible to calculate thepredetermined angle x₂. That is, the above-noted relational expressionsare solved to obtain sin(x₂)=P√2·sin(45−x₂), that is, sin(x₂)=Pcos(x₂)−P sin(x₂), which is then transformed into tan(x₂)=P/(P+1), tothereby make it possible to calculate the predetermined anglex₂=tan⁻¹(P/P+1).

One example of the predetermined angle will be described below inconjunction with an illustrative example.

Illustrative Example

One example of the configuration of an infrared sensor 102 e in anillustrative example will be described below with reference to FIGS. 28and 29.

FIG. 28 is a diagram illustrating one example of the configuration of aninfrared sensor in an illustrative example of the fifth embodiment. FIG.29 is a diagram for describing an inclination of the infrared sensorillustrated in FIG. 28.

The infrared sensor 102 e illustrated in FIG. 27 is one example of theinfrared sensor 102A and is constituted by infrared detection elementsarranged in 8 rows and 8 columns. In the infrared sensor 102 e, some(particular infrared detection elements) of the infrared detectionelements are enabled, and the infrared detection element other than someof the infrared detection elements are disabled.

In this illustrative example, the infrared detection elementsconstituting the infrared sensor 102 e are arranged in 8 rows and 8columns, and the particular infrared detection elements are the infrareddetection elements other than the infrared detection elements at, of the8 rows and 8 columns, two opposite ends in the direction of the scanaxis.

More specifically, the particular infrared detection elementsillustrated in FIG. 28 has a first element column, which includes theinfrared detection elements arranged along a first diagonal line havingthe larger angle relative to the direction of the scan axis of twodiagonal lines of the 8 rows and 8 columns, second element columns,which include the infrared detection elements arranged adjacent to thefirst element column and along the first diagonal line, and thirdelement columns, which include the infrared detection elements arrangedadjacent to the second element columns and along the first diagonalline. That is, of the infrared detection elements constituting theinfrared sensor 102 e, the infrared detection elements in the first tothird element columns are enabled as the particular infrared detectionelements, and the other infrared detection elements are disabled.

The infrared sensor 102 e is also inclined at a predetermined angle (a₂in FIG. 28) relative to the direction of the scan axis. Thepredetermined angle a₂ is an angle adjusted such that all of therespective central positions of the particular infrared detectionelements described above differ from one another, when viewed from thedirection of the scan axis.

Now, a method for calculating the predetermined angle a₂ will bedescribed with reference to FIG. 29, which is a partial diagram of anarea F2 illustrated in FIG. 28, by way of example. In FIG. 29, dottedlines S₂₁, S₂₂, and S₂₃ are parallel to the scan axis. A dotted line L₂₁connects infrared detection elements c₂₁, c₂₃, and c₂₅ and is parallelto the sensor axis. Similarly, a dotted line L₂₂ connects infrareddetection elements c₂₂ and c₂₄ and is parallel to the sensor axis.

In this case, first distances h₃ that are the distances in the directionorthogonal to the direction of the scan axis between the centralposition of a first element (the infrared detection element c₂₃), whichis the infrared detection element belonging to the first element column,and the central positions of third and second elements (the infrareddetection elements c₂₁ and c₂₅), which are the infrared detectionelements that are included in the infrared detection elements adjacentto the infrared detection elements arranged in a row direction having apredetermined angle relative to the direction of the scan axis andincluding the first element (the infrared detection element c₂₃), thatare adjacent to the first element (the infrared detection element c₂₃),and that belong to the third element column, are equal to each other. Inaddition, a second distance that is the distance in the directionorthogonal to the direction of the scan axis between the centralposition of the second element (the infrared detection element c₂₁),which is included in the third and second elements (the infrareddetection element c₂₁ and c₂₅) and corresponds to the tail end in thescan direction, and the central position of a fourth element (theinfrared detection element c₂₄), which is the infrared detection elementthat is included in the infrared detection elements arranged in the rowdirection and including the first element (the infrared detectionelement c₂₃), that is adjacent to the first element (the infrareddetection element c₂₃), that is not adjacent to the third element (theinfrared detection element c₂₁), and that belongs to the second elementcolumn, is equal to the first distance. Additionally, a third distancethat is the distance in the direction orthogonal to the direction of thescan axis between the central position of the fourth element (theinfrared detection element c₂₄) and the central position of a fifthelement (the infrared detection element c₂₂), which is the infrareddetection element that is included in the infrared detection elementsarranged in the row direction and including the third element (theinfrared detection element c₂₁), that is adjacent to the third element(the infrared detection element c₂₁), and that belongs to the secondelement column, is equal to the first distance.

More specifically, as illustrated in FIG. 29, for example, a distance h₃in the direction (in FIG. 29, the vertical direction) orthogonal to thescan axis between the respective central positions of the infrareddetection elements c₂₁ and c₂₃, a distance h₃ in the direction (in FIG.29, the vertical direction) orthogonal to the scan axis between therespective central positions of the infrared detection elements c₂₃ andc₂₅, and a distance h₃ in the direction (in FIG. 29, the verticaldirection) orthogonal to the scan axis between the respective centralpositions of the infrared detection elements c₂₂ and c₂₄ are all equalto each other. For example, the distance in the direction (in FIG. 29,the vertical direction) orthogonal to the scan axis between therespective central positions of the infrared detection elements c₂₁ andc₂₂ is 2h₃ ((“the number of element column”−1)×h₃).

By calculating an angle x₃ that satisfies such a relationship, it ispossible to calculate the predetermined angle a₂. Specifically, such arelationship can be represented as relational expressions:sin(x ₃)=2h ₃ /D ₂sin(z)=h ₃/(√2·D ₂)z=45−x ₃where D₂ represents the distance between the infrared detection elementsand is, for example, the distance (the distance on the sensor axis)between the respective central positions of the infrared detectionelements c₂₁ and c₂₂.

By solving the relational expressions, it is possible to calculate thepredetermined angle a₂. That is, the above-noted relational expressionsare solved to obtain sin(x₃)=2√2·sin(z), that is, sin(x₃)=2 cos(x₃)−2sin(x₃), which is then converted into tan(x₃)=⅔, to thereby make itpossible to determine x₃=33.69°. Thus, the predetermined angle a₂ iscalculated to be 33.69°.

Accordingly, the infrared sensor 102 e is constituted by 8×8 infrareddetection elements that are parallel and orthogonal to the sensor axis,which has an inclination of 33.69° (the predetermined angle a₂) relativeto the scan axis. With this arrangement, of the infrared detectionelements constituting the infrared sensor 102 e and arranged in the 8rows and 8 columns, the respective central positions of the infrareddetection elements in the first to third element columns which areenabled as particular infrared detection elements differ from oneanother, when viewed from the direction of the scan axis, and do notoverlap one another in the direction of the scan axis. Thus, since thenumber of infrared detection elements in the direction orthogonal to thescan axis can be increased in the infrared sensor 102 e, it is possibleto substantially increase the number of pixels of a thermal image in thedirection (the vertical axis) orthogonal to the scan axis.

Although, in the illustrative example, the infrared sensor 102 e hasbeen described as being constituted by infrared detection elements in 8rows and 8 columns, the present disclosure is not limited thereto. Forexample, the infrared detection elements may be infrared detectionelements in 4 rows and 4 columns, infrared detection elements in 32 rowsand 32 columns, or infrared detection elements in 16 rows and 16columns. This is because infrared detection elements in N rows and Ncolumns (N is a natural number greater than or equal to 2) are availableas off-the-shelf products, and thus it is possible to reduce the cost ofemploying the infrared sensor.

FIG. 30 is a diagram for describing an advantage of the infrareddetecting device when the infrared sensor 102 e illustrated in FIG. 27is used.

The infrared sensor 102 e illustrated in FIG. 30 is inclined at 33.69°relative to the direction of the scan axis (i.e., relative to thehorizontal direction). That is, the sensor axis of the infrared sensor102 e is inclined at 33.69° relative to the scan axis. In this case,when the infrared sensor 102 e is rotated (moved) in the direction ofthe scan axis, the particular infrared detection elements in thedirection (the column direction) parallel to the scan axis do notoverlap one another. As a result, the number of particular infrareddetection elements in the direction orthogonal to the scan axisincreases to 34 (34 vertical levels), which is larger than 8 (8 verticallevels), which is the number of infrared detection elements in the rowdirection of the infrared sensor 102 e.

Since the infrared detecting device 1A has the infrared sensor 102 econstituted by the infrared detection elements whose sensor axis isinclined at an angle of 33.69° relative to the scan axis, as describedabove, it is possible to acquire a thermal image having a resolutionthat is 4.25 times as high as that in the comparative example, withoutincreasing the number of infrared detection elements in the infraredsensor 102 e. In addition, when the control processor 12 performs superresolution processing on the thermal image, the infrared detectingdevice 1A can acquire a thermal image having a more enhanced resolution.

[Advantages, Etc. Of Fifth Embodiment]

As described above, according to the infrared detecting device in thepresent embodiment, it is possible to enhance the resolution of thermalimages without increasing the number of infrared detection elementsconstituting the infrared sensor. In addition, in the presentembodiment, since some, not all, of the infrared detection elementsconstituting the infrared sensor are used, there is an advantage in thatit is possible to reduce influences of the comatic aberration and thespherical aberration of the lens used for focusing infrared rays on theinfrared sensor.

The predetermined angle in this case is an angle adjusted such that allof the respective central positions of particular ones of the infrareddetection elements constituting the infrared sensor differ from oneanother, when viewed from a predetermined direction that is the scandirection. For example, when the infrared sensor is constituted byinfrared detection elements in 8 rows and 8 columns, and the infrareddetection elements in the first to third element columns are enabled asthe particular infrared detection elements, the predetermined angle is33.69°.

In this case, when compared with a case in which infrared detectionelements in 8 rows and 8 columns are used, the infrared detectionelements in the three element columns offer an advantage in that thescanning time, that is, the time (the infrared detection time) forscanning the temperature detection range, can be reduced, since thenumber of infrared detection elements that are arranged generallyparallel to the scan axis is small. This also offers an advantage inthat the resolution can be enhanced.

The infrared detecting device in the present embodiment can not onlyreduce the cost of the motor for acquiring a high-resolution thermalimage, as in the fourth embodiment, but also reduce the cost foremploying an infrared sensor having a larger number of infrareddetection elements. The infrared detecting device in the presentembodiment can also offer an advantage in that it is easy to install theinfrared detecting device on other equipment, such as air-conditioningequipment, as a module, as in the fourth embodiment.

Although, in the fourth and fifth embodiments, a case in which theinfrared detection elements are arranged in a matrix with 8 rows and 8columns (8×8) has been described as one example of the infrared sensor102A, the present disclosure is not limited thereto. The infrared sensor102A may be constituted by infrared detection elements arranged in amatrix with 16 rows and 16 columns or with 32 rows and 32 columns or maybe constituted by infrared detection elements arranged in a matrix withN rows and M columns (N and M are natural numbers greater than or equalto 2).

Sixth Embodiment

[Findings Underlying Sixth Embodiment]

Although each of the sensor modules in the first embodiment and so onhas been described above as including the infrared sensor and the lens,the present disclosure is not limited thereto. The sensor module may bea package that accommodates an infrared sensor and an integrated circuit(IC) chip (or an IC element) for performing signal processing on asignal output from the infrared sensor.

In this case, since the IC chip generates heat upon driving, it isnecessary to suppress influences on detection results of the infraredsensor which, the influences being caused by the heat generated in theIC chip.

Accordingly, for example, Japanese Unexamined Patent ApplicationPublication No. 2011-174762 (hereinafter referred to as “Patent Document2”) discloses a configuration in which a wall portion is providedbetween an IC chip and an infrared sensor so as to prevent heatgenerated in the IC chip from being transmitted to the infrared sensor.

However, a sensor module (package) having an infrared sensor is rotatedabout the scan rotation axis to scan a detection range. Thus, dependingon the arrangement of the IC chip and the infrared sensor, there arecases in which heat generated in the IC chip during scanning reaches theinfrared sensor through the atmosphere in the package to therebyadversely affect the detection results of the infrared sensor. That is,in the sensor module (package) disclosed in Patent Document 2, since thearrangement direction (juxtaposition direction) of the IC chip and theinfrared sensor has not taken into account, influences on the detectionresults of the infrared sensor, the influences being caused by heatgenerated in the IC chip, cannot be suppressed during scanning.Consequently, a detection temperature in a detection range scanned bythe infrared sensor may increase owing to the influences of the heatfrom the IC chip, and sensor characteristics of the infrared sensor maydecline.

Accordingly, in a sixth embodiment, a description will be given of aninfrared detecting device that can suppress the influences of heat fromthe IC chip during scanning.

[Configuration of Infrared Detecting Device]

An infrared detecting device in the sixth embodiment will be describedbelow with reference to the accompanying drawings.

FIG. 31 is a diagram illustrating one example of the configuration of aninfrared detecting device 1B in the present embodiment. FIG. 32 is apartial schematic view of a physical configuration when the infrareddetecting device 1B in the present embodiment is attached to thehousing. FIG. 33A is a schematic view illustrating a physicalconfiguration of the infrared detecting device 1B in the presentembodiment. FIG. 33B is a schematic view illustrating another physicalconfiguration of the infrared detecting device in the presentembodiment. Elements that are the same as or similar to those in FIGS. 1to 4 are denoted by the same reference numerals, and detaileddescriptions thereof are not given hereinafter.

Similarly to the case described above and illustrated in FIG. 3, theinfrared detecting device 1B in the present embodiment is attached to ahousing 2 installed on an installation surface 41 that is generallyorthogonal to the bottom surface of space 4 and that is located at apredetermined height from the bottom surface, and acquires thermalimages of a detection range in the space 4.

As illustrated in FIG. 31, the infrared detecting device 1B includes aninfrared detector 20, a scanner 11, and a control processor 12. Theconfiguration of the infrared detector 20 in the infrared detectingdevice 1B illustrated in FIG. 31 differs from that in the infrareddetecting device 1 according to the first embodiment.

[Scanner]

First, a description will be given of the configuration and so on of thescanner 11 in the present embodiment.

The scanner 11 has a scan rotation axis and rotates the infrareddetector 20 about the scan rotation axis to cause an infrared sensor102, which is included in the infrared detector 20, to scan the space 4.

For example, as illustrated in FIG. 33A, the scanner 11 includes a motor111 and a mount base 112 and has a scan rotation axis S1 that isgenerally parallel to the installation surface 41. Under the control ofthe control processor 12, the motor 111 rotates the mount base 112 aboutthe scan rotation axis S1 to thereby rotate the infrared detector 20about the scan rotation axis S1. The infrared detector 20 is mounted onthe mount base 112. As illustrated in FIG. 33A, the mount base 112 isdisposed so as to have an inclination relative to the scan rotation axisS1 and intersects the scan rotation axis S1.

For example, as illustrated in FIG. 33B, the scanner 11 may include amotor 311 and a mount base 312 and have a scan rotation axis S3 havingan inclination relative to the installation surface 41. In this case,under the control of the control processor 12, the motor 311 rotates themount base 312 about the scan rotation axis S3 to thereby rotate theinfrared detector 20 about the scan rotation axis S3. The infrareddetector 20 is mounted on the mount base 312. The mount base 312 isdisposed generally parallel to the scan rotation axis S3.

[Control Processor]

Next, a description will be given of the configuration of the controlprocessor 12 and so on in the present embodiment.

The control processor 12 controls the scanner 11 to process thermalimages (input images) acquired by the infrared detector 20 (the infraredsensor 102) and outputs a resulting thermal image to a computing deviceincluded in the housing 2. The control processor 12 may be included inthe computing device in the housing 2. Since details of processing, suchas distortion correction processing and super resolution processing,performed by the control processor 12 are substantially the same asthose described above in the first embodiment, descriptions thereof arenot given hereinafter. An IC chip 204 (described below) in the infrareddetector 20 may perform the distortion correction processing and thesuper resolution processing.

[Infrared Detector]

Next, a description will be given of the configuration of the infrareddetector 20 and so on in the present embodiment.

FIG. 34 is an exploded perspective view of the infrared detector 20 inthe present embodiment. FIG. 35 is a schematic sectional view of theinfrared detector 20 in the present embodiment.

As illustrated in FIG. 33A or 33B, the scanner 11 rotates the infrareddetector 20 about the scan rotation axis S1 or S3 to thereby cause theinfrared detector 20 to scan a temperature detection range in the space4. In the present embodiment, the infrared detector 20 is a package thataccommodates the infrared sensor 102 and the IC chip 204 such that theyare generally juxtaposed in the direction along the scan rotation axisof the infrared sensor 102. The package corresponds to one aspect of thesensor module in the first embodiment and so on. More specifically, asillustrated in FIG. 34, the infrared detector 20 includes a package mainportion 201, the infrared sensor 102, the IC chip 204, a package lid 205having a window hole 203 therein, and thermistors 207.

The package main portion 201 is formed to have a plate shape, and theinfrared sensor 102 and the IC chip 204 are mounted on one surface ofthe package main portion 201 so as to be generally juxtaposed in thedirection along the scan rotation axis S1 or S3 of the infrared sensor102. The package main portion 201 has two or more thermistors 207 thatare arranged in proximity to the infrared sensor 102 along the scanrotation axis S1 or S3. The package lid 205 that surrounds the infraredsensor 102 and the IC chip 204 is joined to the aforementioned surfaceof the package main portion 201.

For example, an electrically insulating material, such as ceramic or aresin, may be used as a substrate material of the package main portion201. When ceramic is used as the electrically insulating material of thepackage main portion 201, the moisture resistance and the heat thermalresistance of the package main portion 201 can be improved, comparedwith a case in which an organic material, such as an epoxy resin, isused. In addition, the package main portion 201 has a wiring pattern(not illustrated) to which the infrared sensor 102, the IC chip 204, andso on are electrically connected. The package main portion 201 also haselectrodes (not illustrated) for external connection, which areappropriately connected to the wiring pattern. The package main portion201 can be configured with, for example, a ceramic substrate or aprinted wiring board.

As described above, the package lid 205 surrounds the infrared sensor102 and the IC chip 204 and is joined to the aforementioned surface ofthe package main portion 201. The window hole 203 in the package lid 205is located at a position that faces the infrared sensor 102, andinfrared rays travel to the infrared sensor 102 through the window hole203. The window hole 203 is provided with a lens 206 which guidesinfrared light (infrared rays) to the infrared sensor 102.

As described above, the lens 206 is made of silicon, ZnS, or the likehaving a high infrared transmittance. The lens 206 is designed so thatinfrared rays (infrared light) that enter the lens 206 from individualdirections are incident on one or more infrared detection elementsconstituting the infrared sensor 102.

In the present embodiment, the lens 206 has an optical center throughwhich the scan rotation axis S1 or S3 passes. Thus, the infrareddetector 20 (the infrared sensor 102) and the lens 206 are rotated anddriven about the scan rotation axis S1 or S3 that passes through theoptical center of the lens 206.

The present disclosure is not limited to a case in which the scanrotation axis S1 or S3 passes through the optical center of the lens206. The center (lens center) of the arrangement plane of the infraredsensor 102 may have a rotation center through which the scan rotationaxis S1 passes, that is, a rotation center when the infrared sensor 102is rotated about the scan rotation axis S1.

The thermistors 207 are arranged in close proximity to the infraredsensor 102 in the package main portion 201 to detect temperatures on theinfrared sensor 102 and generate analog output voltages corresponding tothe temperatures on the infrared sensor 102. In the present embodiment,the number of thermistors 207 is two or more, and the thermistors 207are arranged in proximity to the infrared sensor 102 along the scanrotation axis S1 or S3. The thermistors 207 output the generated outputvoltages to the IC chip 204. Thermocouples may be used instead of thethermistors 207, as long as they can detect temperatures on the infraredsensor 102.

[IC Chip]

Next, a description will be given of the configuration of the IC chip204 and so on in the present embodiment.

The IC chip 204 is, for example, an application-specific integratedcircuit (ASIC) and performs signal processing on a signal output fromthe infrared sensor 102. The IC chip 204 is not limited to an ASIC andmay be an element into which a desired signal processing circuit isintegrated. The IC chip 204 may be formed using, for example, a siliconsubstrate or may be formed using, for example, a compound semiconductorsubstrate, such as a gallium arsenide (GaAs) substrate or an indiumphosphide (InP) substrate.

In the present embodiment, the IC chip 204 is a bare chip. This isbecause use of a bare chip makes it possible to miniaturize the infrareddetector 20, compared with a case in which a bare chip of the IC chip204 is packaged.

As described above, the IC chip 204 is mounted on the package mainportion 201 in conjunction with the infrared sensor 102. The IC chip 204and the infrared sensor 102 are generally juxtaposed in the directionalong the scan rotation axis of the infrared sensor 102.

In this case, on the basis of output results of two or more thermistors207, the IC chip 204 may perform correction processing on an outputsignal of the infrared sensor 102 and perform signal processing on theoutput signal on which the correction processing was performed. Thus,since the IC chip 204 can perform temperature correction on a thermalimage by using the thermistors 207, the infrared detector 20 can acquirea clearer thermal image having less noise. The IC chip 204 may alsoincorporate some of the functions of the control processor 12 to performsuper resolution processing, as described above.

The IC chip 204 cooperates with the infrared sensor 102. The circuitconfiguration of the IC chip 204 may be appropriately designed accordingto the types of infrared sensor 102 and so on, and may be implementedusing, for example, a signal processing circuit that performs signalprocessing on an output signal of the infrared sensor 102. The followingdescription will be given of one example of the circuit configuration ofthe IC chip 204.

FIG. 36 is a circuit block diagram of the IC chip 204 in the presentembodiment.

As illustrated in FIG. 36, the IC chip 204 includes a first amplifiercircuit 2042 a that amplifies an output voltage of the infrared sensor102, a second amplifier circuit 2042 b that amplifies output voltages ofthe thermistors 207, and a multiplexer 2041 that selectively inputs oneof output voltages of the infrared sensor 102 to the first amplifiercircuit 2042 a. The IC chip 204 further includes an analog-to-digital(A/D) conversion circuit 2043, which converts the voltage, output fromthe infrared sensor 102 and amplified by the first amplifier circuit2042 a, and the voltages, output from the thermistors 207 and amplifiedby the second amplifier circuit 2042 b, into digital values. The IC chip204 further includes a computing unit 2044. By using digital values thatare output from the A/D conversion circuit 2043 in accordance with thevoltages output from the infrared sensor 102 and the thermistors 207,the computing unit 2044 computes the temperature of an object 400. TheIC chip 204 further includes a memory 2045, which is a storage unit forstoring data and so on used in computation performed by the computingunit 2044. The IC chip 204 further includes a control circuit 2046 thatcontrols the infrared sensor 102.

[Configuration of Infrared Sensor]

Next, a description will be given of the configuration of the infraredsensor 102.

The infrared sensor 102 is rotated about the scan rotation axis S1, asillustrated in FIG. 33A, to scan the temperature detection range in thespace 4 and outputs an output signal representing a thermal image (aninfrared thermal image) of the scanned temperature detection range tothe IC chip 204. Specifically, the infrared sensor 102 has one or moreinfrared detection elements arranged in one or more columns and detectsinfrared rays in a temperature detection range in the space 4 scanned bythe one or more infrared detection elements.

The arrangement plane of the one or more infrared detection elements isarranged so as to have an inclination relative to the installationsurface 41. In other words, the arrangement plane is provided so as tohave an inclination relative to the scan rotation axis S1. Thearrangement plane intersects the scan rotation axis S1. Thus, thecentral axis of the field of view of the infrared sensor 102 is directedfrom the direction orthogonal to the installation surface 41 toward thebottom surface, that is, is directed downward, for example, as describedabove and illustrated in FIG. 3.

Thus, the area near and below the position where the infrared sensor 102is disposed is included in the effective viewing angle (angle of view).With the arrangement described above, the infrared sensor 102 in thepresent embodiment can increase the detection range in the area near andbelow the position where the infrared sensor 102 is disposed.

Although a case in which the scan rotation axis S1 or S3 passes throughthe optical center of the lens 206 has been described in the presentembodiment, the rotation center through which the scan rotation axis S1passes, the rotation center being used when the infrared sensor 102 isrotated about the scan rotation axis S1 or S1, may be provided at thecenter (the lens center) of the arrangement plane of the infrared sensor102, not at the optical center of the lens 206.

Also, the arrangement described above in each of the second to fifthembodiments may be employed as an arrangement of the infrared detectionelements constituting the infrared sensor 102. Examples of thearrangement of infrared detection elements constituting the infraredsensor 102 will be described below with reference to the accompanyingdrawings.

FIGS. 37, 38, 39A, and 39B are schematic views illustrating examples ofthe arrangement of infrared detection elements included in the infraredsensor in the present embodiment. Elements that are the same as orsimilar to those in FIGS. 2, 19A, 20, and so on are denoted by the samereference numerals, and detailed descriptions thereof are not givenhereinafter.

First Arrangement Example

For example, the infrared sensor 102 and the IC chip 204 may bejuxtaposed (or generally juxtaposed) in the direction along the scanrotation axis S1 (or the scan rotation axis S3) of the infrared sensor102, as illustrated in FIG. 37, and the columns of the infrareddetection elements constituting the infrared sensor 102 may be arrangedalong the direction of rotation about the scan rotation axis S1.

Second Arrangement Example

For example, the infrared sensor 102 may also be an infrared sensor 102a illustrated in FIG. 38. That is, as illustrated in FIG. 38, theinfrared sensor 102 a and the IC chip 204 may be juxtaposed (orgenerally juxtaposed) in the direction along the scan rotation axis S1(or the scan rotation axis S3) of the infrared sensor 102 a, and thecolumns of the infrared detection elements constituting the infraredsensor 102 a may be arranged so as to have an inclination at apredetermined angle relative to the direction of rotation about the scanrotation axis S1 (or the scan rotation axis S3). The “predeterminedangle” in this case refers to an angle adjusted such that all of therespective central positions of the infrared detection elementsconstituting the infrared sensor 102 a are different from one another,when viewed from the direction of rotation about the scan rotation axisS1 (or the scan rotation axis S3). Since the predetermined angle anddetails of the infrared sensor 102 a are substantially the same as thosedescribed above in the fourth and fifth embodiments, descriptionsthereof are not given hereinafter.

The infrared sensor 102 a configured as described above makes itpossible to substantially increase the number of pixels in the directionorthogonal to the scan rotation axis S1, as described above in thefourth embodiment and so on. That is, the infrared sensor 102 a makes itpossible to enhance the resolution in the direction orthogonal to thescan rotation axis S1, without increasing the actual number of infrareddetection elements constituting the infrared sensor.

Third Arrangement Example

For example, the infrared sensor 102 may be an infrared sensor 402 aillustrated in FIG. 39A. That is, as illustrated in FIG. 39A, theinfrared sensor 402 a may be such that infrared detection elements arearranged in two or more columns in the arrangement direction of theinfrared sensor 402 a and the IC chip 204, and the two or more columnsare offset from each other in the arrangement direction. In the exampleillustrated in FIG. 39A, the two or more columns in the infrared sensor402 a are offset from each other such that the column that is closer toa leading end in the direction of rotation about the scan rotation axisS1 (or the scan rotation axis S3) is closer to the IC chip 204.Alternatively, the two or more columns in the infrared sensor 402 a maybe offset from each other such that the column that is closer to theleading end in the direction of rotation about the scan rotation axis S1(or the scan rotation axis S3) is farther from the IC chip 204. In theexample illustrated in FIG. 39A, the infrared detection elements in 8rows and 8 columns are arranged, and the infrared detection elements inthe adjacent columns are offset by a ⅛ pixel.

An example in which the infrared detection elements in the adjacentcolumns are arranged offset from each other (pixel-offset arrangement)is not limited to the infrared sensor 402 a illustrated in FIG. 39A. Forexample, the infrared sensor may be an infrared sensor 402 b illustratedin FIG. 39B or may be an infrared sensor 402 c illustrated in FIG. 39C.More specifically, as illustrated in FIG. 39B, in the infrared sensor402 b, infrared detection elements in 16 rows and 4 columns arearranged, and the infrared detection elements in the adjacent columnsare offset from each other by a ¼ pixel. Also, as illustrated in FIG.39C, in the infrared sensor 402 c, infrared detection element in 32 rowsand 2 columns are arranged, and the infrared detection elements in theadjacent columns are offset from each other by a ½ pixel.

In the infrared sensor 402 a and so on configured as described above,the number of pixels in the direction orthogonal to the scan rotationaxis S1 (or the scan rotation axis S3) can be substantially increased,as described above in the second embodiment. That is, it is possible toenhance the resolution in the direction orthogonal to the scan rotationaxis S1, without increasing the number of infrared detection elementsconstituting the infrared sensor.

Fourth Arrangement Example

Also, for example, as in the infrared sensor 202 and so on describedabove in the second embodiment and illustrated in FIGS. 7, 9, 10, and11A to 15, the infrared sensor 102 may have a plurality of infrareddetection elements arranged in one or more columns and be formed suchthat the horizontal edge of each of the infrared detection elements ineach column, the horizontal edge being generally parallel to the bottomsurface 42, has a smaller dimension as the infrared detection element islocated closer to the bottom surface 42. Since details are substantiallythe same as those described above in the second embodiment, descriptionsthereof are not given hereinafter.

According to the infrared sensor 202 and so on described above, evenwhen the rotational speeds of the infrared detection elements in eachrow in the infrared sensor 202 whose central axis of the field of viewis inclined relative to the scan rotation axis S1 are different fromeach other, the scan densities (resolutions) from the upper end to thelower end can be made equal to each other, as described above in thesecond embodiment. This offers an advantage in that distortioncorrection on the thermal images is not necessary.

Advantages, Etc. of Sixth Embodiment

As described above, according to the present embodiment, it is possibleto realize the infrared detecting device 1B that can suppress influencesof heat from the IC chip 204 during scanning.

The advantage of being able to suppress influences of heat from the ICchip 204 during scanning will now be described with reference to theaccompanying drawings.

FIG. 40A is a schematic view for describing influences of heat from theIC chip 204 during scanning in the comparative example. FIG. 40B is aschematic view for describing influences of heat from the IC chip 204during scanning in the infrared detecting device in the presentembodiment. In FIGS. 40A and 40B, a description will be given inconjunction with the infrared sensor 402 b illustrated in FIG. 39B,since the same can be true for the (oblique) infrared sensor 102 ahaving an inclination like that described above in FIG. 38 and for theinfrared sensor 402 a (in the pixel-offset arrangement) and so on inwhich the infrared detection elements in the adjacent columns are offsetfrom each other like that described above in FIGS. 39A to 39C. In FIGS.40A and 40B, the infrared detection elements constituting the infraredsensor 402 b are assigned numbers (1, 2, 3, 4, 5, 6, 7, 8, . . . , 63,and 64) sequentially from the top.

For example, the IC chip 204, which is an ASIC, generates heat. In thearrangement of the IC chip 204 and the infrared sensor 402 b in thecomparative example illustrated in FIG. 40A, a temperature differenceoccurs toward the direction of rotation about the scan rotation axis(i.e., in the horizontal direction in FIG. 40A). Consequently, there isa problem in that, when a thermal image is acquired using the infraredsensor 402 b (described above and illustrated in FIG. 39B) in which thepixels in the adjacent columns are offset from each other and issubjected to the super resolution processing, lateral-stripe noiseoccurs in a thermal image that has been subjected to the superresolution processing. For example, whereas the temperature of aninfrared detection element with number 4 is low, the temperature of aninfrared detection element with number 5 becomes high, and thus atemperature difference occurs therebetween. That is, a temperaturedifference occurs between the infrared detection elements with adjacentnumbers. When such a temperature difference occurs in a lateraldirection (i.e., the rotation direction and the scan direction), anunfavorable processing result due to, for example, generation oflateral-stripe noise, such as a jagged pattern, is output when the superresolution processing is performed.

On the other hand, in the arrangement of the IC chip 204 and theinfrared sensor 402 b in the present embodiment illustrated in FIG. 40B,a temperature difference occurs in the direction along the scan rotationaxis (i.e., in the vertical direction in FIG. 40B). In this case, sincethe temperatures of the infrared detection elements increase in theorder of numbers 1, 2, 3, . . . , 63, and 64, the temperature differencebetween the infrared detection elements with the adjacent numbersbecomes small. Accordingly, even when the super resolution processing isperformed on an acquired thermal image, it is possible to suppresslateral-stripe noise that occurs in the thermal image that has beensubjected to the super resolution processing. That is, the infrareddetecting device in the present embodiment can suppress influences ofheat from the IC chip 204 during scanning.

FIG. 40B illustrates an example in which the IC chip 204 is disposeddirectly below the infrared sensor 402 b. That is, FIG. 40B illustratesan example in which the angle θ (not illustrated) between the scanrotation axis and a line (hereinafter, a first line) that connects anapproximate central position of the infrared sensor 402 b and anapproximate central position of the IC chip 204 is 0°. The presentdisclosure, however, is not limited to this example, and the infraredsensor 402 b and the IC chip 204 may be generally juxtaposed in thedirection along the scan rotation axis of the infrared sensor 402 b. Theexpression “generally juxtaposed” as used herein refers to, for example,an arrangement in which the angle θ between the scan rotation axis andthe first line satisfies—45°<θ<+45°. In other words, it is sufficient tohave an arrangement that satisfies “the angle between the first line andthe scan rotation axis”<“the angle between the first line and thedirection orthogonal to the scan rotation axis”. When the influences ofthe above-described temperature difference are considered, it is moredesirable to satisfy −15°<θ<+15°.

In addition, for example, the infrared detector 20 may havetemperature-measuring elements that are capable of detecting thetemperatures on the infrared sensor 402 b. Examples of the temperaturemeasuring elements include thermistors and thermocouples. With such anarrangement, on the basis of output results of two or more thermistors207, the IC chip 204 can perform correction processing on a signaloutput from the infrared sensor 402 b and perform signal processing onthe output signal on which the correction processing is performed. Thatis, the IC chip 204 corrects influences of heat from the IC chip 204 onthe basis of output results of two or more thermistors 207 to therebysuppress the influences, thus making it possible to output a clearerthermal image. Hence, there is an advantage in that, even when the superresolution processing is performed subsequently, it is possible toacquire a thermal image having less lateral-stripe noise.

FIGS. 41A and 41B are schematic views illustrating examples of anarrangement of the thermistors 207 in the present embodiment. When theinfrared detecting device 1B in the present embodiment uses twothermistors 207, for example, they are arranged as illustrated in FIG.41A. For example, the two thermistors 207 are arranged at left side ofthe infrared detecting device 1B, as illustrated in FIG. 41A.Alternatively, the two thermistors 207 may be arranged at right side ofthe infrared detecting device 1B. Also, the two thermistors 207 arearranged along the scan rotation axis S1 (or the scan rotation axis S3).When the infrared detecting device 1B in the present embodiment uses sixthermistors 207, for example, they are arranged as illustrated in FIG.41B. As illustrated in FIG. 41B, for example, three thermistors 207 arearranged at left side of the infrared detecting device 1B and along thescan rotation axis S1 (or the scan rotation axis S3), and threethermistors 207 are arranged at right side of the infrared detectingdevice 1B and along the scan rotation axis S1 (or the scan rotation axisS3).

As described above, the infrared detecting device in the presentembodiment includes an infrared sensor that has one or more infrareddetection elements arranged in one or more columns and an IC chip thatperforms signal processing on a signal output from the infrared sensor,and the infrared sensor and the IC chip are generally juxtaposed in thedirection along the scan rotation axis of the infrared sensor.

This can realize the infrared detecting device 1B that can suppressinfluences of heat from the IC chip 204 during scanning. Thus, theinfrared detecting device 1B can acquire a clearer thermal image inwhich the amount of noise due to heat from the IC chip 204 is small.

Also, for example, the infrared detecting device 1B further includes apackage main portion having one surface on which the infrared sensor andthe IC chip are mounted.

For example, when the infrared sensor 102 or the like, which may be asensor chip, and the IC chip 204, which may be an ASIC, are configuredin a single package, a wiring line that connects the infrared sensor 102or the like and the IC chip 204 can be shortened, and thesignal-to-noise ratio (SNR) can be increased.

For example, the package main portion may have a package lid joined tothe surface so as to surround the infrared sensor and the IC chip; thepackage lid may have, at a position that faces the infrared sensor, awindow hole through which an infrared ray travels to the infraredsensor; and the window hole may be provided with a lens which guidesinfrared light to the infrared sensor.

In addition, for example, the infrared detecting device may furtherinclude a lens which guides infrared light to the infrared sensor. Thelens may have an optical center through which the scan rotation axispasses, and the package main portion and the lens may be rotated aboutthe scan rotation axis that passes through the optical center.

This allows the rotation center of the infrared sensor 102 or the likeand the optical center of the lens 206 to substantially match eachother, thus making it possible to clarify the boundary between ahigh-temperature area and a low-temperature area in a thermal imageacquired by the infrared sensor 102 or the like. Meanwhile, the largerthe displacement between the rotation center of the infrared sensor 102or the like and the optical center of the lens 206 is, the less clearthe boundary between the high-temperature area and the low-temperaturearea in the thermal image becomes. This is because, with a thermal imagein which the boundary between a high-temperature area and alow-temperature area is not clear, objects, such as people, cannot berecognized with higher accuracy. Thus, this configuration allowsobjects, such as people, in a thermal image acquired by the infraredsensor 102 or the like to be recognized with higher accuracy.

For example, the infrared sensor may be rotated about the scan rotationaxis to scan a detection range, and the one or more columns in theinfrared sensor may be arranged so as to have an inclination at apredetermined angle relative to a direction of rotation about the scanrotation axis.

In this case, for example, the predetermined angle may be an angleadjusted such that all of the respective central positions of theinfrared detection elements constituting the infrared sensor differ fromone another, when viewed from a direction of rotation about the scanrotation axis center.

This makes it possible to enhance the resolution in the directionorthogonal to the scan rotation axis, without increasing the actualnumber of infrared detection elements constituting the infrared sensor102 or the like.

For example, the infrared detection elements in the infrared sensor maybe arranged in two or more columns in an arrangement direction of theinfrared sensor and the IC chip, and the two or more columns may beoffset from each other such that the column that is closer to a leadingend in a direction of rotation about the scan rotation axis is closer toor farther from the IC chip.

For example, the infrared detecting device may further include two ormore thermistors. The two or more thermistors may be arranged inproximity to the infrared sensor along the scan rotation axis, and basedon an output result of the two or more thermistors, the IC chip mayperform correction processing on a signal output from the infraredsensor and perform signal processing on the output signal on which thecorrection processing is performed.

Since this arrangement allows temperature correction on the thermalimage to be performed using the thermistors, it is possible to acquire aclearer thermal image having less noise.

For example, the infrared detecting device may be attached to a housinginstalled on an installation surface that is generally orthogonal to abottom surface of space and that is located at a predetermined heightfrom the bottom surface, and an arrangement plane of the one or moreinfrared detection elements may be arranged so as to have an inclinationrelative to the installation surface.

For example, the scan rotation axis may be generally parallel to theinstallation surface, and the arrangement plane may intersect the scanrotation axis.

This arrangement makes it possible to increase the detection range inthe area near and below the position where the infrared detecting device1B is disposed.

For example, the scan rotation axis and the arrangement plane may beprovided so as to have the above-described inclination relative to theinstallation surface, and the arrangement plane may be generallyparallel to the scan rotation axis.

With such an arrangement, when the infrared sensor 102 or the like isrotated about the scan rotation axis, the rotational speed (therotational pitch) at the upper end and the rotational speed at the lowerend, viewed from the bottom surface of the infrared sensor, become equalto each other, thus making the distortion correction unnecessary. Sinceit is not necessary to perform the distortion correction, the amount ofmemory used and the amount of computational load can be further reduced.

Although the infrared detecting devices according to one or more aspectsof the present disclosure have been described above based on theembodiments, the present disclosure is not limited to the embodiments.Modes obtained by applying various modifications conceived by thoseskilled in the art to the embodiments or modes constituted by combiningconstituent elements in different embodiments may also be encompassed bythe scope of one or more aspects of the present disclosure, as long assuch modes do not depart from the subject matter of the presentdisclosure. For example, the present disclosure also encompasses casesas described below.

(1) FIGS. 42A and 42B illustrate examples of the shape of the infrareddetection elements constituting the infrared sensor. For example,although described above in the second embodiment with reference to FIG.14 and so on, the infrared sensor in one aspect of the presentdisclosure may be an infrared sensor 402 d configured with a pluralityof infrared detection elements whose dimensions are each graduallyreduced, as illustrated in FIG. 42A. Also, the infrared sensor in oneaspect of the present disclosure may be an infrared sensor 402 eillustrated in FIG. 42B. More specifically, the infrared sensor 402 emay be such that infrared detection elements in two or more columns arearranged in the arrangement direction of the infrared sensor 402 e andthe IC chip 204 (not illustrated), and the number of two or more columnsdecreases for every same or different number of rows, as the distance toone end in the arrangement direction of the infrared sensor 402 e andthe IC chip 204 decreases. That is, the number of infrared detectionelements in each row illustrated in FIG. 42B may decrease, as thedistance of the row to the IC chip 204 decreases. Alternatively, thenumber of infrared detection elements in each row may decrease, as thedistance of the row to the IC chip 204 increases.

(2) In the above-described embodiments and so on, the angles, the size,and so on of each infrared sensor have been described as examples, andthey are not limited to the examples. Even when the infrared sensor hasangles, a size, and so on that do not conform to those described above,it is also encompassed by the scope of the present disclosure, as longas the same or similar effects are obtained.

(3) Each device described above may be, specifically, a computer systemincluding a microprocessor, a read-only memory (ROM), a random-accessmemory (RAM), a hard disk unit, a display unit, a keyboard, a mouse, andso on. A computer program is stored in the RAM or the hard disk unit.The microprocessor operates in accordance with the computer program, sothat each device realizes its functions. The computer program in thiscase is made of a combination of a plurality of instruction codes forgiving instructions to a computer in order to achieve a predeterminedfunction.

(4) Some or all of the constituent elements included in each devicedescribed above may be implemented by one system large-scale-integrated(LSI) circuit. The system LSI is a super-multifunctional LSImanufactured by integrating a plurality of constituent elements on onechip and is, specifically, a computer system including a microprocessor,a ROM, a RAM, and so on. The computer program is stored in the RAM. Themicroprocessor operates in accordance with the computer program, so thatthe system LSI realizes its functions.

(5) Some or all of the constituent elements included in each devicedescribed above may be implemented by an integrated circuit (IC) card ora single module that can be inserted into and removed from the device.The IC card or the module may be a computer system including amicroprocessor, a ROM, a RAM, and so on. The IC card or the module mayinclude the aforementioned super-multifunctional LSI. The microprocessoroperates in accordance with the computer program, so that the IC card orthe module realizes its functions. The IC card or the module may betamper-proof.

(6) The present disclosure may also be implemented by the methodsdescribed above. Those methods may also be realized by a computerprogram implemented by a computer or may be realized using digitalsignals provided by the computer program.

In the present disclosure, the computer program or the digital signalsmay be recorded on computer-readable recording media, for example, aflexible disk, a hard disk, a CD-ROM, a magneto-optical (MO) disk, adigital versatile disk (DVD), a DVD-ROM, a DVD-RAM, a Blu-ray® Disc(BD), and a semiconductor memory. Those methods may also be realized bythe digital signals recorded on the recording media.

Additionally, in the present disclosure, the computer program or thedigital signals may be transmitted over a telecommunication channel, awireless or wired communication channel, a network typified by theInternet, data broadcasting, or the like.

Moreover, the present disclosure may be realized by a computer systemincluding a microprocessor and a memory, the memory may store thecomputer program, and the microprocessor may operate in accordance withthe computer program.

The present disclosure may also be implemented by another independentcomputer system by transporting the recording medium on which theprogram or the digital signals are recorded or transferring the programor the digital signals over the network or the like.

(7) The above-described embodiments and the modifications may also becombined together.

The present disclosure can be applied to an infrared detecting devicefor acquiring high-resolution thermal images and can be particularlyapplied to an infrared detecting device attached to other equipment,such as air-conditioning equipment, as a module and used for controllingthe equipment.

What is claimed is:
 1. An infrared detecting device comprising: aninfrared sensor that has one or more infrared detection elementsarranged in one or more columns; and an integrated circuit (IC) chipthat performs signal processing on a signal output from the infraredsensor, wherein the infrared sensor and the IC chip are generallyjuxtaposed in a direction along a scan rotation axis of the infraredsensor.
 2. The infrared detecting device according to claim 1, furthercomprising: a package main portion having one surface on which theinfrared sensor and the IC chip are mounted.
 3. The infrared detectingdevice according to claim 2, wherein the package main portion has apackage lid joined to the surface so as to surround the infrared sensorand the IC chip; the package lid has, at a position that faces theinfrared sensor, a window hole through which an infrared ray travels tothe infrared sensor; and the window hole is provided with a lens whichguides infrared light to the infrared sensor.
 4. The infrared detectingdevice according to claim 1, wherein the infrared sensor is rotatedabout the scan rotation axis to scan a detection range, and the one ormore columns in the infrared sensor are arranged so as to have aninclination at a predetermined angle relative to a direction of rotationabout the scan rotation axis.
 5. The infrared detecting device accordingto claim 4, wherein the predetermined angle is an angle adjusted suchthat all of respective central positions of the infrared detectionelements constituting the infrared sensor differ from one another, whenviewed from the direction of rotation about the scan rotation axis. 6.The infrared detecting device according to claim 1, wherein the infrareddetection elements in the infrared sensor are arranged in two or morecolumns in an arrangement direction of the infrared sensor and the ICchip; and the number of two or more columns decreases for every same ordifferent number of rows, as a distance to one end in the arrangementdirection of the infrared sensor and the IC chip decreases.
 7. Theinfrared detecting device according to claim 1, wherein the infrareddetection elements in the infrared sensor are arranged in two or morecolumns in an arrangement direction of the infrared sensor and the ICchip; and the two or more columns are offset from each other such thatthe column that is closer to a leading end in a direction of rotationabout the scan rotation axis is closer to or farther from the IC chip.8. The infrared detecting device according to claim 1, furthercomprising: two or more thermistors, wherein the two or more thermistorsare arranged in proximity to the infrared sensor along the scan rotationaxis; and based on an output result of the two or more thermistors, theIC chip performs correction processing on a signal output from theinfrared sensor and performs signal processing on the output signal onwhich the correction processing is performed.
 9. The infrared detectingdevice according to claim 1, wherein the infrared detecting device isattached to a housing installed on an installation surface that isgenerally orthogonal to a bottom surface of space and that is located ata predetermined height from the bottom surface; and an arrangement planeof the one or more infrared detection elements is arranged so as to havean inclination relative to the installation surface.
 10. The infrareddetecting device according to claim 9, wherein the scan rotation axisand the arrangement plane are arranged so as to have the inclinationrelative to the installation surface, and the arrangement plane isgenerally parallel to the scan rotation axis.
 11. The infrared detectingdevice according to claim 9, wherein the scan rotation axis is generallyparallel to the installation surface, and the arrangement planeintersects the scan rotation axis.
 12. The infrared detecting deviceaccording to claim 11, wherein the infrared detection elements in theinfrared sensor are arranged in one or more columns; and a horizontaledge of each of the infrared detection elements in each column, thehorizontal edge being generally parallel to the bottom surface, has asmaller dimension, as the infrared detection element is located closerto the bottom surface.
 13. The infrared detecting device according toclaim 12, wherein the infrared detection elements in the infrared sensorare arranged in three or more columns; a horizontal edge of each of theinfrared detection elements in each column, the horizontal edge beinggenerally parallel to the bottom surface, has a smaller dimension, asthe infrared detection element is located closer to the bottom surface;and a distance between central positions of the infrared detectionelements at corresponding portions in the adjacent columns of the threeor more columns is constant.
 14. The infrared detecting device accordingto claim 13, wherein positions of the topmost infrared detectionelements in the three or more columns, viewed from the bottom surface,are sequentially offset toward the bottom surface.
 15. The infrareddetecting device according to claim 14, wherein the position of thetopmost infrared detection element in one column is offset from thetopmost infrared detection element in the column adjacent thereto byone-fourth of a dimension of a vertical edge of the topmost infrareddetection element in the adjacent column, the vertical edge beinggenerally orthogonal to the bottom surface.
 16. The infrared detectingdevice according to claim 12, wherein the infrared detection elements inthe infrared sensor are arranged in three or more columns; thehorizontal edge of each of the infrared detection elements in each ofthe column, the horizontal edge being generally parallel to the bottomsurface, has a smaller dimension, as the infrared detection element islocated closer to the bottom surface; and each of the infrared detectionelements in each of the three or more columns is located closer to acenter of the three or more columns in a column direction, as theinfrared detection element is located closer to the bottom surface. 17.The infrared detecting device according to claim 11, wherein arelationship given by L_(x)/L_(y)=sin(θ_(x))/sin(θ_(y)) is satisfied,where L_(x) represents a dimension of a horizontal edge of one of theinfrared detection elements in each column, L_(y) represents a dimensionof a horizontal edge of the infrared detection element that is adjacentto the one infrared detection element at a bottom surface side, θ_(x)represents an angle between the scan rotation axis and a main light rayat a lowest end that is included in an angle of view of the one infrareddetection element and that is closest to the bottom surface, and θ_(y)represents an angle between the scan rotation axis and a main light rayat a lowest end that is included in an angle of view of the adjacentinfrared detection element.
 18. The infrared detecting device accordingto claim 11, wherein a relationship given byL_(x)/L_(y)>sin(θ_(x))/sin(θ_(y)) is satisfied, where L_(x) represents adimension of a horizontal edge of one of the infrared detection elementsin each column, L_(y) represents a dimension of a horizontal edge of theinfrared detection element that is adjacent to the one infrareddetection element at a bottom surface side, θ_(x) represents an anglebetween the scan rotation axis and a main light ray at a lowest end thatis included in an angle of view of the one infrared detection elementand that is closest to the bottom surface, and θ_(y) represents an anglebetween the scan rotation axis and a main light ray at a lowest end thatis included in an angle of view of the adjacent infrared detectionelement.
 19. The infrared detecting device according to claim 11,wherein a relationship given by L_(x)/L_(y)<sin(θ_(X))/sin(θ_(y)) issatisfied, where L_(x) represents a dimension of a horizontal edge ofone of the infrared detection elements in each column, L_(y) representsa dimension of a horizontal edge of the infrared detection element thatis adjacent to the one infrared detection element at a bottom surfaceside, θ_(x) represents an angle between the scan rotation axis and amain light ray at a lowest end that is included in an angle of view ofthe one infrared detection element and that is closest to the bottomsurface, and θ_(y) represents an angle between the scan rotation axisand a main light ray at a lowest end that is included in an angle ofview of the adjacent infrared detection element.